Apple Tree Leaf Growth/Disease? Cedar-Apple Rust?

Question: Can anyone help me identify what is wrong with this apple tree and how to cure it. Most of the leaves have these. Yellow/orange spots on top and growths on the bottom of the leaves under those spots. I took the best pictures I could with my phone's focus. My best guess from research is cedar-rust. There are definitely a lot on the property, but none nearby. Didn't notice this in the spring when I mulched and fertilized.
Answer: I'm afraid it is Cedar Apple Rust, the common term used for Gymnosporangium juniperi-virginianae, a fungal infection which requires both apple/crabapple and juniper plants to complete its life cycle. There aren't really an ideal solutions, nothing that will kill it off, so the usual course is to keep a check on Junipers and prune out any galls seen before they get to the orange, gelatinous stage and ready to disperse their spores.
Now you've got it, you will need to carry out preventative measures, such as checking the junipers, possibly even removing them, sweeping  up and clearing away any leaf litter from them and the apple trees, using preventive fungicidal sprays, which may give some control. More info here https://www.planetnatural.com/pest-problem-solver/plant-disease/cedar-apple-rust/
Comment: Will this kill the tree, this year, or will it just set it back? Does it repeat the following year, or can I start an anti fungal regimen next spring and not have to worry about it. Thanks.
Comment: Unlikely to kill it, but it won't be terribly healthy and it may affect fruit production. Now you've got it, you will always have to worry about it and take evasive action - its a never ending two year cycle all the time you've got both apple and juniper in the same area.
Comment: I've been having trouble with it for a long time. I might just rip it up and replace it with a resistant tree. It's only about 3' tall. Had it for several years and it's been one thing after the other. Inch worms, this, something else. I've got aphids on my other one I have to take care of.
Comment: Well its a thought, but bear in mind 'resistant' doesn't necessarily mean impervious or immune... if you take that one out, might be worth waiting a year or two to try to break the existing cycle.


What is the best way to simulate grief?

Question: I am new to the art of writing and have been wondering if there is a way to introduce the grief of loss(character dies) in my story, inturn while making the reader feel the grief. Is there a good method to go about doing this (Making the reader feel the grief a character feels)?
Comment: My best advice is that if you want a reader to truly grieve they need to feel a personal connection with both the grieving character and the grieved. If you already have this you're doing great. If you don't yet I suggest waiting before going in for the kill.
Comment: Please try to use existing tags rather than creating new ones.
Comment: Ok... Sorry, I didn't know...
Comment: Sometimes a new tag *is* needed. For example, recently a new user wanted to ask about writing food recipe books, and we had no tag that was anywhere in the vicinity, except for the all-encompassing [tag:non-fiction]. But if your question can fit under a slightly broader tag, like [tag:emotions], there's usually no need for a more specific tag. If you're unsure, you can always ask on [writing.meta.se]. We have many discussions related to tags there.
Answer: It is more engendering grief in the reader than simulating it, but one must be careful lest the beloved character you killed off be the only one the reader cares about. It is one thing for the reader to put the book down for a few minutes and think about the loss, quite another for them to put it down and never pick it up again.
What you need to inspire in the reader is genuine sorrow that said character died balanced with caring how the others will cope without him/her. Will their quest fail without this character or will this loss galvanize them further.
When Katherine Kurtz killed the gentle healer Rhys, it shocked me. She had another character psychically linked with him at the time of his death so that he was not alone. This other character cared deeply for Rhys and his anguish seemed real. It made the death matter.
Killing off a good and interesting character must be important or the reader feels they wasted time investing more in the character than the author did.
Comment: Thank you! I never thought of it in this way! Thanks a lot!
Answer: The best way I know of is to make the reader feel the grief too. By this I mean you build the character so well, make them so loved, that when they die it hurts. Then the reader doesn't just imagine what the other characters are feeling, they feel it too.

What is the best way to simulate grief?


Was Yitro a prophet?

Question: Yitro is such an important tzaddik in the Torah, I was wondering if he is a prophet?
Comment: @user12119 There's a _parasha_ named after _Balaq_ and he's the opposite of a _tzadik_.
Comment: How do you know he was such a tzaddik?
Comment: R. Netanel ibn al-Fayumi quotes the Sages as referring to Yitro as a prophet.
Comment: @sabbahillel He is a Temani Rishon from about 850 years ago. He quotes this from Chazal, so his greatness is not really the issue, but rather the greatness of Chazal. The Temanim retained many Midrashim that were lost to other communities.  "As our sages of blessed memory explain, "Seven prophets prophesied to the nations of the world before the giving of the Torah: Laban, Jethro, Balaam, Job, Eliphaz, Bildad and Zophar." From Bustan al-`Uqul. Cited [here](http://judaism.stackexchange.com/a/25666/8775).
Comment: I mean they even made a parsha with his name in it!Even Moses or aharon didn't have a parsha named after themselves.
Comment: @mevaqesh Please cite who he is and where he writes this. Where do we see he is a valid source like Rashi, Rambam, or Rav Ovadiah Yosef.
Answer: @mevaqesh cites נתנאל בירב פיומי as having said.

"Seven prophets prophesied to the nations of the world before the
  giving of the Torah: Laban, Jethro, Balaam, Job, Eliphaz, Bildad and
  Zophar."

The gemara Bava Basra 15b (ArtScroll 15b1 top of the page) gives a different list which does not include Yisro.

Seven Prophets prophesied for the nations of the world and these are:
  Bil'am, his father, Iyov (Job), Elifaz the Teimanite, Bildad the
  Shuchite, and Tzofar the Na'amassite and Elihu the son of Berachel the
  Buzite (the four friends who came to console Iyov).

Yisro is not listed among the known prophets sent to the Bnai Yisrael. Before Sinai only Avraham Yitzchak Yaakov Moshe and Aharon are listed in List of Jewish Prophets After Sinai it continues with Yehoshua, Pinchas, Elkanah, Eli, Shmuel, etc.
Thus Yisro is not listed as one of them, nor is he explicitly called a prophet in the Torah. he has a parsha named for him because of his advice to Moshe and his behavior.
One should note that just as there were many prophets sent to Bnai Yisrael whose names were not included, there could have been others sent from among the nations whose names are not included and Yisro could have been among them.
Note that Adam, Noach, Shem and Eiver are not in the lists. We see that Rivkah went to "inquire of Hashem" about the problems with her pregnancy. The implication seems to be that she went to ask a prophet. Note that even if one says that she "asked" directly and was granted a prophesy, she is not in the list of 7 female prophets.
While there were many others, their names are not passed down to us.

The Talmud (Megillah 14a) says that there had been twice as many
  prophets as the number of people who left Egypt (2,600,000), but only
  those whose messages were for future generations were recorded. This
  count was 48 male and 7 female Prophets.
Of course, there is much debate about who is included in the list.
  Rashi (Megillah 3a) suggests that Daniel wasn't a prophet and should
  be replaced by Shemaia, who told Rehavam not to go to war with Yeravam
  and the northern kingdom. Rabbein Hananel and the Vilna Gaon start
  from Moshe and add in the sons of Korach.
Rashi also comments that "two [of the prophets] I don't know,"
  referring to numbers 47 and 48. Another commentator says the missing
  two prophets are Oded and Hanani Haroeh.
Comment: What is Prohets and Prophecy? Why do you assume that it the authoritative work on the topic, whose silence answers the question?
Comment: `Before Sinai only Avraham Yitzchak Yaakov Moshe and Aharon are listed in Prophets and Prophecy` Well obviously this list leaves much to be desired, as the Torah records God speaking to Adam, yet he is not listed. If you claim that he wasn't a proper prophet by some undefined benchmark, then you reduce your answer to a matter of semantics: these are the prophets who are the real prophets, as defined by the prophets that are included in the list. There is no reason to assume that the OP meant anything other than whether he prophesied; not whether his prophecy had some unspoken characteristic.
Comment: @mevaqesh  This is a quote from a valid summary website which gives the list of prophets as given in the talmud and medrashim as well as rashi. There are other sites as well. The point is that Yisro is not listed in the "official" list of know neviim. that is all that I was saying. I could have given other sites as well but it was not needed. You can google for others.
Comment: We do know that there were other prophets besides for those listed/counted as one of the 48 prophets, those whos propesy was not given also for future generations
Comment: @SamuelManuel yes, that is what I said, I just answered the question that Yisro is not listed among the known prophets. Also the medrash of 600,000 prophets speaks of those after har Sinai and entry into the land. Note that the elders (and Eldad and Medad) are not spoken of as prophets but as those granted prophesy fo a limited time).
Comment: @mevaqesh I included your citation and also the list from bava basrah. Note that Adam, Noach and Shem are not included in the liat from the talmud and torah. I would suppose that the definition of prophet would be another question and would be dealt with by the Rambam among others. I am just giving the lists of prophets, not all individuals who Hashem spoke with (such as Avimelech and Par'o in the time of Avraham).

Was Yitro a prophet?


What transform can I use to "zoom" in a specific portion of a signal's spectrum?

Question: If I recall correctly, there is a variation of the DFT that can be used to analyze a specific band of the spectrum of a signal. How is it called?
Comment: [It is called the Chirp-Z-Transform.](http://en.wikipedia.org/wiki/Bluestein's_FFT_algorithm)
Comment: @Mohammad: "One common question is : Is the zoom FFT the same as the chirp z-transform. The answer is : Absolutely not." http://www.numerix-dsp.com/zoomfft.html  Would be a good answer to explain the relationship.
Comment: @endolith Not the same sure, but they are different ways of arriving at the same end result. The 'Zoom-FFT' involves downsampling / BPF / FFT, whereas the Chirp-Z Transform evaluates the Z-transform on the band you want. I have heard people refer to 'Chirp-Z' as 'Zoom-FFT' as in its particular application.
Answer: You're probably referring to the zoom FFT. It's essentially a technique that allows for complexity reduction in the case where you have a small portion of a larger band that you'd like to analyze at high spectral resolution. It prevents you from having to calculate the high-resolution frequency content in the bands that you don't care about. Roughly, the algorithm can be summarized as follows:

Apply a bandpass filter around the region of interest, eliminating the components outside the band that you care about.
Decimate the signal by a factor $D$, such that the resulting sample rate still meets the Nyquist criterion for the filter's passband width. Depending upon where the band's center frequency was, this process might also involve frequency-translating the signal to baseband.
Perform a DFT on the signal. In order to get the same frequency resolution at the output, the "zoomed" transform only requires a transform length that is $\frac{1}{D}$-th of what you would need to use if you used the original, unfiltered signal for your analysis.


Non-PAE system updating to PAE kernels?

Question: I just had an Ubuntu system of mine completely die on me after upgrading it and now I am confused.
Basically, it is an older machine (Intel P3, 512MB RAM, etc) that I use as a command line only test bed. It's CPU does NOT support PAE extensions. PAE is mandatory when installing 12.04 LTS so what I basically did was install 11.10 x86 and then updated to 12.04 LTS and that worked fine. It even detected the CPU didn't support PAE, ignored the PAE kernels, and updated all the relevant non-PAE packages correctly (including using non PAE kernels under 12.04 LTS).
Fast forward a few months as I hadn't used the thing so I wanted to update it. Did apt-get update and it listed a bunch of packages including a new kernel. At the top, it did saw something along the lines of "these packages are being ignored" and then listed several *PAE packages. So I proceeded with the update as everything it was going to do look OK to me, however, the update failed (see screenshot below) and now the machine won't even boot.

What is going on? Is it not possible to update 12.04 LTS anymore on non-PAE machines? How come it tried to (seemingly) update *PAE packages when my CPU can't support them? I feel like this is the root of the problem but if you have any other idea's or suggestions, please mention them!
Answer: I would not recommend Ubuntu for a PC with a non PAE core.  If you can get it to run performance is unlikely to be satisfactory.
You can however use Lubuntu 12.04 on non PAE systems.  Lubuntu is a much lighter desktop than Ubuntu but as you use it mainly from the command line it should be fine for your needs and its supported in this forum.
Download is here
http://cdimage.ubuntu.com/lubuntu/releases/12.04/release/
Lubuntu 12.10 requires a PAE however.
If you want to try installing Ubuntu 12.04 on a non PAE system however Take a look here.

Non-PAE system updating to PAE kernels?


Which fret do I place a capo on, to play Eb music using C chords?

Question: If the sound of the music is in the key of Eb and I want to play using chord shapes in the key of C, what fret do I put the capo on?
Comment: @BobBroadley I think it's better to have an unambiguous question, even if it's not what the OP meant! All the answers are general enough to still apply if OP wants to transpose in the other direction. And thanks for the +1
Comment: @slim, I think you've edited the question to match the meaning behind the question, but I thought it better not edit it too much, just in case the OP meant something else... +1 for your answer BTW.
Comment: @Linda - tell us exactly which chords you want to play. There may be an alternative solution.
Answer: This depends upon what you mean by "music is in the key of…" and "I want to play it in the key of…".
If you mean that you want to play chords written in the key of C and have them sound in the key of Eb, put the capo on fret 3. Eb is three semitones higher than C (C-C#-D-Eb). (This seems likely.)
If you want to play chords written in the key of Eb and have them sound in the key of C, put the capo on fret 9. C is nine semitones higher than Eb (Eb-E-F-F#-G-G#-A-Bb-B-C). (This seems less likely.)
(Reading between the lines, I'm guessing that you actually want to change chords written in Eb, to be played in C, but still sounding in Eb - in which case, there is more about this in the third and fifth bullet points below.)
Each fret on a guitar is a semitone higher than the one below it (or one semitone higher than the open string, for fret 1). To find out where to position a capo for any particular transposition, work out how many semitones higher the key you want the music to sound in is from the key you want to play chords written in.
Here's an example: suppose you are playing chords in D Major, but you want the music to sound in B Major; you have to go up nine frets and so place the capo at fret 9 (D-D#-E-F-F#-G-G#-A-A#-B).
A few things to note:

the key you are wanting to transpose to may actually be closer to the key you want to play in by moving downwards. For instance, you can transpose D Major to B Major by moving down three frets. But you can't actually use a capo to transpose in this way, as you can't put a capo lower than an open string!
You can easily work out any required transposition by using this sequence of chromatic pitches:
C - C#/Db - D - D#/Eb - E - F - F#/Gb - G - G#/Ab - A - A#/Bb - B - C (Note that here I have given both the flat and sharp name for each of the notes between the natural notes; e.g. F# is the same as Gb.) If you need to move "further" than the end of the sequence (eg. A Major to D Major), you simply continue counting up from the low C once you get to the high C. As you can see, it is quite easy to remember the pattern of chromatic pitches, without even seeing a list such as this: every pair of natural notes has a note with a sharp and flat name between them except E-F and B-C (e.g. the note between D and E is called either D# or Eb).
if the music is already written down in the key you want the music to sound in, but you want to change the chords to be played in an easier key, you have to "reverse" the direction of semitone counting, to write down the chords you will actually play. For instance, if your music is written in Eb Major and you want it to sound in Eb Major, but you want to play chords in C Major (which is much easier!), you need to count down three semitones from each chord in your music, to work out which chords you'll be playing once the capo is on fret 3. It's much easier in this case to actually write the transposed chords next to (or above) the original chords in your music, as it can be really tricky to count semitones for the transposition while trying to read music too! So, an Eb chord would be rewritten and played as a C chord if the capo is on fret 3; an F chord would be rewritten and played as a D chord if the capo is on fret 3 etc.

The reason these two approaches are needed when using a capo (counting up and counting down), is because there are two main reasons for transposing using a capo:

you may already know how to play a song on the guitar in a particular key, probably using "easy" chords. A singer may want you to transpose to another key to make the music fit their range better (or you may be playing with a transposing instrument, for instance). This requires you to count up the semitone distance from the key you want to play in to the new key. You then put your capo at this fret and carry on playing the same chords, which now sound in a different key.
on the other hand, you may want to simplify a written chord part to play it in an easier key, but without changing the sounding pitch of the music. In this case, you need to count down the semitone distance from the key the music is originally written in, to the key you want to play in, put the capo at this fret, and then rewrite the chords by similarly counting down from each of the original chords by the same number of semitones.
Comment: I realised that this is a bit of an ambiguous question, so I've heavily edited my answer, and tried to approach this from several angles...
Comment: @scrowler, I think the OP wants to *play* chords in C, but keep them *sounding* in the original written key of Eb, so you would put the capo on fret 3. Like I say, this is an ambiguous question. So much so, I'm answering it again, to try to get a clearer answer… (Watch this space…)
Comment: @scrowler - for a song using Eb, I would happily use a C shape barre chord on the 3rd fret for it. Where's the problem in substituting the barre finger with a capo ? However, then an F chord would inevitably appear, and probably need to be barred...
Comment: 3rd fret capo wouldn't give you access to chords that would normally be on Eb as the chords would probably be barre chords anyway. Unless there is already a capo position that isn't mentioned yet. Eg Eb would be a barre chord without a capo so putting a capo on third fret would still require a barre chord, but not in the same position
Comment: @scrowler - Putting a capo on the third fret means playing a C chord form yields an Eb chord. D minor form yields Fm, Em form gives you Gm, Ab form gives you Cm, and so on. You can also put a capo on the 6th fret, but that's less optimal for some players.
Comment: @neilfein I realise that, but if the original song is in Eb, you wouldn't be playing a C shape, you'd be playing an Eb barre chord from the 6th fret. Putting a capo onto the 3rd fret doesn't let you play this song in C any easier, if anything that chord shape would be more useful it there were no capo applied at all. OP wants to play in C, not in Eb any more...
Comment: Agreed, on a second reading this question is ambiguous.
Comment: Hello both, see what you think of my other answer; I reckon it's a bit clearer...
Comment: @Bob - the question is ambiguous, but you've provided clear answers. Not the easiest one to elucidate on, bet he wasn't expecting such complicated explanations !
Comment: @Tim novices learn a non-barred 4 string F shape (presumably for playing along with their novice-pianist friends).
Comment: @slim - you're right ! It's one I can't remember ever teaching. Baptism by fire into barre chords !
Answer: Although your question is a little ambiguous, I'm guessing that you want to play music written in Eb, using chords in C, but keeping the music sounding in Eb. So, you put the capo on fret 3 and rewrite all your chords three semitones lower. However, just giving you this answer won't help you understand how to work out where to put a capo should you need to work out a different transposition, so what follows is a description of how to work out which fret to place a capo on for any particular transposition.
There are three things to consider when using a capo to transpose guitar music: the key the original music is written in; the key you want to play chords in; the key you want the music to sound in.
Usually you will only need to consider two of these, for instance: 1. using a capo to play written chords so that they sound at a different pitch; 2. using a capo to play chords in an easier, different key to the original music, but staying at the same pitch as the original music. However, it is possible to change both the chords played and the sounding pitch of the original music.

If you want to change the chords played (usually to make them easier), but keep the music sounding at the same pitch, count down by semitones from the original key to the key you want play in, place the capo at this fret, then rewrite all the chords by counting down by the same number of semitones. For instance, to play music written in Eb, using chords in C, but keeping the music sounding in Eb, place the capo at fret 3, as C is three semitones lower than Eb (C-C#-D-Eb). Then, rewrite all chords three semitones lower, for example: Eb becomes C; Fm becomes Dm; Bb becomes G.
If you want to change the sounding pitch without changing the chords you play (to accommodate the range of a singer, perhaps), count up by semitones from the original key to the new sounding key. For instance to play chords written in A, but so that they sound in D, you place the capo at fret 5, as D is five semitones higher than A (A-Bb-B-C-C#-D). You then continue to play the same chords, but they now sound in a different key.

As I say, these are the most likely ways to use a capo. You could, though, change the chords played and the sounding pitch from the original key. This is a little more complicated. Firstly, count down by semitones from your original, written key to the key you want to play in and rewrite all chords this number of semitones lower; secondly, count up by semitones from the key you want to play in to the key you want the music to sound in and place the capo at this fret.
Here's an example: the music is written in Eb, you want to play in A and have the music sound in F. Firstly, count down from Eb to A, that's six semitones, rewrite all chords six semitones lower. Secondly, count up from A to F, that's eight semitones, so place the capo on fret 8. Voila, chords originally written in Eb, played in A, sounding in F…
Finally, a couple of things to note:
I only mention transposing chords here, to transpose single notes you wouldn't usually need a capo, instead you would simply move up or down the required number of frets.
Here is the list of chromatic pitches, to help you count up or down by semitones (notes between natural notes are listed with both their flat and sharp names):
C - C#/Db - D - D#/Eb - E - F - F#/Gb - G - G#/Ab - A - A#/Bb - B - C
If you need to count "further" than the beginning or end of the sequence, you simply continue counting from the opposite end.
Answer: E♭ is three semitones above C. So you should put the capo on the third fret.
Some of the other answers are quite thorough, but it is really a simple answer!
Comment: Lol, three! Very simple!
Answer: I think the other answers are good, but wanted to condense the most important bit into one answer. You just have to count the semitones.
Here are all the notes, and the number of semitones they are away from A.

0  1  2  3  4  5  6  7  8  9  10 11 12
A  A# B  C  C# D  D# E  F  F# G  G# A
A  Bb B  C  Db D  Eb E  F  Gb G  Ab A

D is five semitones up from A -- so if you want to play an A shape and have it sound like a D, put a capo on the 5th fret.
Eb is three semitones up from C -- so if you want to play a C shape and have it sound like an Eb, put a capo on the 3rd fret.
This formula works for any pair of keys. Note that to play an A shape and get a G sound, you have to capo the 10th fret, which turns your guitar into a soprano instrument with a very short fretboard. It can sound nice, but may not be what you want -- in which case you have to choose a different set of chord shapes, or tune down (see below)

You can do the same thing at the instrument by making the chord shape and shifting it up.

Play an open C chord. Say "This is a C".
Move it up a fret. "This is a C#". (if you want to play this now, you can only pluck the fretted strings -- or, if you can, change the fingering and barre it)
Move it up again, "This is a D"
Keep moving up until you reach the target chord.
Put the capo on the fret below your new chord, to make the open strings play the right notes (if you were barreing, the capo goes where your barre is)

A capo can only shift the tuning up, not down. If you want to go down, you can change the tuning on your guitar. For example, to play E shapes and hear Eb shapes, just tune every string down by one semitone.
Doing this will reduce the tension of your strings. Playing will feel different. The timbre of the guitar will change. Intonation might be affected. Lower than 2 semitones down and these effects become quite pronounced. Keep going lower and the guitar will become unplayable -- of course there will come the point where the strings are completely slack.
Answer: Simple, completely effective answer:
For Eb, don't use a capo. Rather, lower the tuning of each string. Re-tune the strings, low to high, Eb, Ab, Db, Gb, Bb, Eb. Then play the regular chord shapes that you already know.
Comment: Question states (we think!) that she wants to play C shapes. Downtuning by one requires using E shapes. If arbitrary (but easy) shapes are OK, then I'd say capo 1st fret and play D shapes.
Comment: I agree with you and Slim! I would suggest tuning a half step down, but the OP does ask to play with C shapes.
Answer: I think I know exactly what you mean, so I will just give a simple answer in case you are confused by the others (but I highly recommend studying them, anyway).
The answer is to place the capo over the 3rd fret.  This makes your "C Chord shape" (what you would play to get a C chord should there be no capo at all) be an Eb chord.  Thus, you can easily access the key of Eb now.


Learn penetration testing in home environment without a lot of money

Question: I saw this post How to learn penetration testing at home? and I decide to ask about my self. I want to get into cyber security. So the post I send is about web security, I'm not interested in it. I had cover those topics:
Basic programming on C, intermediate(I can write a few tools that are helpful for example brute-force scrit) in python, I can read assembly code, and write basic programs I'm familiar with the most structures in assembly language I mean the stack, heap global variables. I know who to use wireshark diffrent kind of flags(SYN ACK etc..) but I'm not very good at analyzing them I mean for example if the FTP connection isn't on port 23 it will be hard for me to understand that this connection is FTP, also I can understand the most of the banners. I have more experience with Linux than Windows, but I can administrate simple server on windows, also I had exploit more Windows than linux actually the only linux machine I had exploit is metasploitable. I had exploit windows xp and 7 with different exploits. I can use Nessus and OpenVAS, I can't get nexpose. I'm familiar with metasploit framework i can use the most of the modules. I'm also familiar with cryptography I can recognize a few hash algorithms, I'm familiar with most used techniques to exchange key for example Diffie–Hellman mythology, the public key infrastructure etc. I'm also familiar with DOD and OSI model but not very deep I understand how they work, also I learn electronics in school so I'm familiar with analog circuits, I can solder use multimeter I'm familiar with the most of elements(I mean transistor, diods etc..) and I know for what are they used and how are they used, from C and ASM I'm familiar with stack and heap overflow, I know little about integer overflow and format string exploitation. So tell me how to continue. I'm really unfamiliar with web exploitation I can use a few automated tools but I can't find XSS on my own(I had tried a few times one success and a lot of fails =D). Also I had never practice in real environment I mean I hadn't pen test real company I'm kind afraid of I may do something wrong a the company lose money which I should recover. So please give me hint what to learn, I can't pay for expensive course, also I don't think that CEH will give me skills I mean they don't have any pre-requirements about their students and is kind of stupid to teach to overflow people who write to python and had never touched C.
Comment: It's hard to give you advise what to learn next without knowing what your actual goal is.
Answer: If you have the motivation and perseverance you don't need any expensive course at all. The only thing courses will give you which you cannot gain any other way is certificates. Now if your wanting to get into a corporate business of some kind these will be vital to you securing a role most of the time. My perception is experience and understanding are much more valuable than a piece of paper, but the problem is how do you show that.
I can help you out with a few resources that have helped me a lot learning about infosec:
VulnHub is an extensive resource for not only links to great sites but it hosts a wide variety of virtual machines you can let loose on and gain/improve on your skills.
Pentesterlab is similar to Vulnhub but offers more in depth information and VM's. Also this site has a nice tab called bootcamp which can be usefull as what to learn each week.
SecurityTube One of the most extensive infosec video sites out there. The owner of this site is a great mentor and offers great tutorials from basic to advanced. There is a LOT out there on the internet and you can use google to your advantage. Hope this helps you a little.
Answer: you (and others are invited too) could try and start webhacking here @ fump.8ack.org, which is a service that has some intentionally vulnerable apps available

Damn Vulnerable WebApp
Exploit-KB
Multillidae
SQLOL
WackoPicko


Why can you have the method definition inside the header file in C++ when in C you cannot?

Question: In C, you cannot have the function definition/implementation inside the header file. However, in C++ you can have a full method implementation inside the header file. Why is the behaviour different?
Answer: In C, if you define a function in a header file, then that function will appear in each module that is compiled that includes that header file, and a public symbol will be exported for the function. So if function additup is defined in header.h, and foo.c and bar.c both include header.h, then foo.o and bar.o will both include copies of additup.
When you go to link those two object files together, the linker will see that the symbol additup is defined more than once, and won't allow it.
If you declare the function to be static, then no symbol will be exported. The object files foo.o and bar.o will still both contain separate copies of the code for the function, and they will be able to use them, but the linker won't be able to see any copy of the function, so it won't complain. Of course, no other module will be able to see the function, either. And your program will be bloated up with two identical copies of the same function.
If you only declare the function in the header file, but do not define it, and then define it in just one module, then the linker will see one copy of the function, and every module in your program will be able to see it and use it. And your compiled program will contain just one copy of the function.
So, you can have the function definition in the header file in C, it's just bad style, bad form, and an all-around bad idea.
(By "declare", I mean provide a function prototype without a body; by "define" I mean provide the actual code of the function body; this is standard C terminology.)
Comment: It is not such a *bad*  idea - this sort of things can be found even in the GNU Libc headers.
Comment: @papiro The problem is, that wrapping only protects during a single run of the compiler. So if foo.c is compiled to foo.o in one run, bar.c to bar.o in another, and foo.o and bar.o are linked into a.out in a third (as is typical), that wrapping doesn't prevent multiple instances of it, one in each object file.
Comment: but what about the idiomatic wrapping of the header file in a conditional compilation directive?  Then, even with the function declared AND defined in the header, it will only get loaded once.  I am new to C, so I may be misunderstanding.
Comment: Isn't the problem described here what `#ifndef HEADER_H` is supposed to prevent?
Comment: @DavidConrad, Defining a method/function in a header in c++ provides faster linking if the compiler decides to inline it. So this should be done if you have a short one-line function, especially if the function is templated (avoiding headaches by maintaining use cases in the cpp file). The cost of inlining a method at the link stage is expensive, and unlike compiling an inline function for each translation unit,  the expense of inlining at the link stage is present **for all** rebuilds, so scales badly.
Answer: C and C++ behave very much the same in this regard -- you can have inline functions in headers. In C++, any method whose body is inside the class definition is implicitly inline. If you want to do the same in C, declare the functions static inline.
Comment: "_declare the functions `static inline`_"... and you'll still have multiple copies of the function in each translation unit that uses it. In C++ with non-`static` `inline` function you'll have only one copy. To actually have the  implementation in the header in C, you must 1) mark the implementation as `inline` (e.g. `inline void func(){do_something();}`), and 2) actually say that this function will be in some particular translation unit (e.g. `void func();`).
Comment: Do functions that are declared in the class, but defined in another .cpp file also implicitly get marked as ```inline```?
Comment: @TylerShellberg, no, the definition (not just the declaration) needs to be inside the class definition for the method to be implicitly `inline`.
Answer: The concept of a header file needs a little explanation:
Either you give a file on the command line of compiler, or do an #include.
Most of the compilers accept a command file with extension c, C, cpp, c++, etc. as the source file. However, they usually include a command-line option to enable usage of any arbitrary extension to a source file also.
Generally the file given on the command line is called 'Source', and the one included is called 'Header'.
The preprocessor step actually takes them all and makes everything appear like a single big file to the compiler. What was in the header or in the source is actually not relevant at this point. There is usually an option of a compiler which can show the output of this stage.
So for each file that was given on the compiler command line, a huge file is given to the compiler. This may have code/data which will occupy memory and/or create a symbol to be referenced from other files. Now each of these will generate an 'object' image. The linker can give a 'duplicate symbol' if the same symbol is found in more than two object files which are being linked together.  Perhaps this is the reason; it's not advised to put code in a header file, which can create symbols in the object file.
The 'inline' are usually inlined .. but when debugging they may not be inlined. So why does the linker not give multiply defined errors? Simple... these are 'weak' symbols, and as long as all the data/code for a weak symbol from all the objects are same size and content, the linked will keep one copy and drop copy from other objects. It works.
Answer: You can do this in C99: inline functions are guaranteed to be provided somewhere else, so if a function was not inlined, its definition is translated into a declaration (i.e., implementation is discarded). And, of course, you can use static.
Answer: C++ standard quotes
The C++17 N4659 standard draft 10.1.6
"The inline specifier" says that methods are implicitly inline:

4 A function defined within a class definition is an inline function.

and then further down we see that inline methods not only can, but must be defined on all translation units:

6 An inline function or variable shall be defined in every translation unit in which it is odr-used and shall
  have exactly the same definition in every case (6.2).

This is also explicitly mentioned in a note at 12.2.1 "Member functions":

1 A member function may be defined (11.4) in its class definition, in which case it is an inline member function (10.1.6) [...]
3 [ Note: There can be at most one definition of a non-inline member function in a program. There may be
  more than one inline member function definition in a program. See 6.2 and 10.1.6. — end note ]

GCC 8.3 implementation
main.cpp
struct MyClass {
    void myMethod() {}
};

int main() {
    MyClass().myMethod();
}

Compile and view symbols:
g++ -c main.cpp
nm -C main.o

output:
                 U _GLOBAL_OFFSET_TABLE_
0000000000000000 W MyClass::myMethod()
                 U __stack_chk_fail
0000000000000000 T main

then we see from man nm that the MyClass::myMethod symbol is marked as weak on the ELF object files, which implies that it can appear on multiple object files:

"W"
  "w" The symbol is a weak symbol that has not been specifically tagged as a weak object symbol.  When a weak defined symbol is linked with a normal defined symbol, the normal defined symbol is used with no error.  When a weak undefined symbol is linked
                 and the symbol is not defined, the value of the symbol is determined in a system-specific manner without error.  On some systems, uppercase indicates that a default value has been specified.
Answer: Probably for the same reason that you must put the  full method implementation inside the class definition in Java.
They might look similar, with squiggly brackets and many of the same keywords, but they are different languages.
Comment: No, it was designed to have "A High degree of C compatibility", and "No gratuitous incompatibilities with C". (both from Stroustrup).  I agree that a more in-depth answer could be given, to highlight why this particular incompatibility is not gratuitous.  Feel free to supply one.
Comment: No, there is actually a real answer, and one of the primary goals of C++ was to be backward compatible with C.
Comment: I would have, but Simon Richter already had when I posted that.  We can quibble about the difference between "backward compatible" and "A High degree of C compatibility", but the fact remains that this answer is incorrect.  The last statement would be correct if we were comparing C# and C++, but not so much with C and C++.


Will enemies with Wizard spells have spellbooks a PC Wizard can learn from?

Question: I'm aware that Wizards can learn spells from other spellbooks and scrolls they find, as long as they take the time and money to learn it. If there is an enemy, such as a Mage that is listed in the Hoard of the Dragon Queen supplement, that is listed as a caster and said to have Wizard Spells, does this mean we can assume they are a Wizard class and they have to have a spellbook? Is there any chance a PC Wizard could learn the spells off this defeated enemy?
Comment: I've edited your title to actually correspond to your question. Your question presently just asks about whether enemy Wizards will have spellbooks, whilst your title was implying a general-case question about every source a Wizard can learn from.
Comment: Edited again, that's a fair distinction to make. (But I mainly edited the title because "Where can wizards learn spells from?" is a very different question with very different answers to what you're asking about here.)
Comment: Thanks. I kept it broad because the enemy isn't specifically listed as a wizard, just says it has wizard spells. I was wondering if there was a distinction.
Answer: As you say, a Wizard can learn spells from spellbook they find. So the question here is whether wizardly enemies will have spellbooks on them when they are defeated.
That's entirely up to the DM. Like any piece of loot, any enemy could be carrying a spellbook for whatever reason. If the DM wants the players to find the defeated Mage's spellbook, they will. There are a multitude of reasons for why a Mage would or wouldn't be carrying their spellbook on their person - it's the DM's choice to give the players access to this (fairly valuable) piece of treasure or not.
Remember that a Wizard doesn't require their spellbook to cast their spells (unless they want to cast them as rituals), so it's perfectly reasonable for a Mage to have hidden their spellbook somewhere once they prepared their day's spells.
So if you're asking this as a DM, the answer is that it's up to you. If you're asking as a player, the answer is that it's up to the DM, but it might well be worth your while to search the lairs/houses/dens/homes/castles/towers/whatever of enemy Mages you defeat.
Answer: It's up to the DM, but it is dependent on which feature they use to cast spells whether or not they would use a spellbook
According to the Monster Manual introduction, if a monster has the Spellcasting feature then they have class levels:

A monster with the Spellcasting class feature has a spellcaster level and spell slots

The other ways that monsters can cast spells, or produce spell like effects are through the Innate Spellcasting or Psionics features described in the MM introduction.
If we take one of the spellcasters from the Lost Mine of Phandelver (LMoP)

 Glasstaff

as an example. Their stat block states:

 Spellcasting. The mage is a 4th-level spellcaster that uses Intelligence as its spellcasting ability (spell save DC 13; +5 to hit with spell attacks). The mage knows the following spells from the wizard's spell list: [...]

They use the wizard's spell list, and have class levels, and thus is a xth level wizard (see the spoiler for the exact level).
By virtue of them being a wizard, they require a spellbook to prepare their spells. They do not however require a spellbook to cast spells they prepared in the last long rest they had access to a spellbook.
The Monster Manual also says:

A stat block rarely refers to equipment, other than armor or weapons used by a monster.
[...]
You can equip monsters with additional gear and trinkets however you like, using the equipment chapter of the Players Handbook for inspiration and you decide how much of a monster's equipment is recoverable after the creature is slain and whether any of that equipment is still usable.
[...]
If a spellcasting monster needs material components to cast its spells, assume that it has the material components it needs to cast the spells in its stat block.

As a result we have two possible options:

The designers didn't bother to put in the spellbooks because they didn't think it important to the adventure/assumed the DM would know to include this after having read the Monster Manual (in which case you should add a spellbook with appropriate spells.
The wizards presented have lost their spellbooks and are only able to cast the spells that they last prepared until they replace their spellbook (in which case there is no spellbook to recover).

Were I to run this adventure as a DM, I would use option 1 and add in any additional spells as appropriate for the particular NPC. For example:

 Glasstaff is brewing potions of invisibility, so it makes sense for them to have Invisibility in their spellbook.
Answer: I'd say it entirely depends on the NPC wizard, in question. If they are just "built for the moment", something for the party to fight, and probably kill, if you are doing well, and if he just needs access to the spells he'll cast, then no, he probably won't. If he's part of a group, or has a lair, he can, conceivably, prepare his spells, leave his precious book at home, and be good as gold.
My understanding of spell prep, in this edition, is that the wizard only needs his books to change his prepared spells, after a long rest. So long as he likes what he's got, he doesn't need the book; the next day, his mana recharges, and he's got the slots back. He still has the same prepped spelss as yesterday. If he needs something different, then he needs to heft the heavy tome, thumb through it, and recommit words, gestures, and such, to his memory. If he has a safe place to leave it, I'd leave it, rather than the cliche "party got captured, and lost all their loot." Especially in a new world where magic items are rare again, losing mundane gear is a hassle, but losing your only copy of your spellbook...no thanks.
If your NPC wizard is "important", such as a recurring villain, who harasses the party regularly, and improves as they do, I'd say it's a bit more likely he could have the book on him. If he's likely to do ritual casting, setting traps for you, or some such, he might even need to. Defeating this enemy could justify acquiring his books of spells, making it a worthy addition to your treasure pull, and let's be fair, it's what the wizards want (especially if scrolls are also rare). If he's "just a schlub", though, I'd say he probably doesn't have it, and you'd need to find the fort he came from, or tower he resided in. My "typical" War Wizard of Cormyr, for instance, is learned enough to be pretty sure what his ideal array for battlefield casting will be, and leave his tome safely in the barracks; if he doesn't die, and things change, he can get back to it.
As an aside, I wonder if there is any reason a wizard with a suitably strong familiar couldn't have it "hold" his spellbook(s), dismiss it into whatever pocket dimension it resides in, and then call it up to peruse his book, when convenient. Seems easier than dragging several heavy books around, or several other options. I might've just found another reason to like familiars. ;)
Comment: You may find [this](http://rpg.stackexchange.com/q/61979/15469) interesting reading.
Comment: Yes I did, and thanks. Sad it's not a concrete "yes" or "no" type of thing, but that does leave it nicely open to try and persuade a GM of, at least.  At 3 lbs. a piece, and with the wizard having the best options for knowing the most spells, even if scrolls are impractical, in 5e, it just seems that a decent wizard would need a place to store their small box-set of books, where they'd be safe, but accessible, when needed. Certainly a bit OP, when I imagine how many mcguffins a party might hide this way, or some bad guys, but I like the idea, in my head.
Comment: I like the idea, too, but given that the only way to do it if you can't with your familiar is the 8th-level spell *Demiplane*, you're probably not meant to be able to do it with the 1st-level *Find Familiar*.
Comment: Hmm, I wonder what the best option is, then? The wizard is potentially unique in that (s)he needs those clunky books, or at least access to them, but they don't *do* anything, on their own; if they needed their books to cast, like the Archmage, in Gargoyles, needed the Grimoirum Arcanorum, to use its power, it might be more justified, but they don't. No one else lugs around so much stuff they don't use, and the wizard isn't the young man, with the strong back, I imagine carrying a bag full of books, around. Oh well, have a horse, or have a wagon, right? (*Bag of holding*, if lucky ;) )
Comment: It's one book, hardly the major issue you're imagining.
Comment: What is needed to make a spare spellbook is stated in the PHB.  Any competent wizard that isn't impoverished would have spares stashed somewhere safe, and probably carry his working spellbook on any journey of more than a day.


Writing a novel, can I do [this or that]?

Question: I want to write a novel about [something or other] and now I wonder if it is possible to do [this or that].
Comment: This is a question that this site **actually** needs. Too many questions revolve around it. +1
Answer: You almost certainly can. At very least, if this is a project that appeals to you, then you can try, and see how it goes.
There have been stories and novels written in second-person future tense, written without the letter 'e', written in the form of a series of exercise and relaxation tapes, written from the viewpoint of a sentient pregnancy test. There is probably nothing quite so outlandish or restrictive that it could not possibly be written well.
The question is not "Can it be done." The questions are:

Why do you want to?
Is it worth the effort?
What will you do to make it work?
Does it work?

Why do you want to?
There are a few main reasons to try to do something very unusual:

Because you want an unusual result. That's fine. This means you're experimenting, and deliberately creating something odd. The question isn't "can it be done," it's an experiment. It may not work out, or the unusual result may not turn out to be a good piece of fiction -- but you're not going to write unusual fiction without spending some time writing weird stuff and seeing what works.
Because it sounds like a challenge. That's fine. Just bear in mind that the fact that something is challenging to write, doesn't mean it's interesting to read. Try it, see if it gets your creative juices flowing or if the challenge is enjoyable to you, and if it's not doing that, you can stop.
Because it's necessary for the specific story you want to tell. These can be very challenging to write, but what helps is that you have a specific goal in mind. Knowing where you're headed goes a long way towards helping you overcome the difficulties you've taken on; it gives you a way to constantly check yourself, see that the story is doing what you want it to be doing, even if what you want it to be doing is fairly unusual.

Is it worth the effort?
Once you know why you're trying to do [this or that], you can make up your mind on whether it's actually worth your time and effort.
If you're doing it just because it sounds hard, you are the sole arbiter of how hard you want your writing to be, and how hard for you doing [this or that] actually is.
If this is some huge constraint imposed by your story, you're the only one who really understands what it is you're trying to accomplish, and how the story might work even under such constraints.
And so forth.
What will you do to make it work?
This is going to be the really tough one. Because you've made up your mind, made your choice, and now you're trying to write something very unusual.
OK. That's fine. It's a hard problem. Maybe you've cut yourself off from some easy answers.
The point is, deal with specific difficulties, concrete individual phrases or characters or plot points you can grapple with. Don't leave it at "Doing [this-or-that] sounds hard". It's not a yes/no question; it's a series of "How do I solve this?".
Does it work?
A lot of the time, there's no real way to tell if you're doing well until you're done.
That's when you can look at the story or the novel as a whole, and see if, as a whole, you've managed to make the hard thing work well.
You can look at it. Beta readers can look at it. You can get meaningful feedback and opinions, based on how well you did the hard thing.
And then you can adjust. If you didn't get it right, maybe with the entire thing in hand, you can tweak and edit now so that it does work. Or, maybe now you come to the conclusion that you don't know how to make it work. That's fine too; plenty of stories and books come out poorly, even the ones that weren't Herculean tasks. Having written something that doesn't work is not a failure, unless you're already under contract. You stretched yourself; you tried something new; you experimented. That's how you get better, and find interesting stuff.

And that, I think, is as close to an answer as you'll get.
Nothing is impossible to write. Lots of things are hard to write. (Almost anything, really.) You may or may not have the skill, at this point, to write something really difficult that you want to write.
Weigh your options. Be aware of the choices you are making. Accept that some of writing is experimenting, and it's absolutely fine if plenty of it doesn't come out very well.
And good luck. :)
Answer: <code>GLENDOWER
I can call spirits from the vasty deep.

HOTSPUR
Why, so can I, or so can any man;
But will they come when you do call for them?
</code>
-- Henry IV, part 1 | Act 3, Scene 1
In other words, "Can I do ..." is always the wrong question. "Will anyone want to read ..." is the right question.
And if you can't think of a dozen widely read books where the author does [something or other] then the answer is no.
Storytelling is the most ancient of arts. It neither needs nor rewards innovation. It is all about excellence of execution. If you are spending your time and energy on anything else, you are wasting your time.
Comment: Good answer, Mark, but yes and no. There is writing to reach a mainstream audience, and there is writing to titillate the avant-garde; there is writing to make money, and there is writing to fulfill a personal vision; there is writing as a job, and there is art. And some writing manages to be both, to surprise readers, and become a new standard. Storytelling *has* changed fundamentally from Homer to advertising and video games. But for what I write, and for what I believe this site is about – which, I think, is marketable writing –, I agree with your answer.
Comment: But it is worth pointing out that both the act of writing and the act of storytelling are inherently transitive. They are acts of communication. So in fact you cannot do these acts purely for yourself. If you are not thinking of a reader, you are not communicating. You are doing something else with words, but it is not writing. In other words, it is masturbation, not love.
Comment: So true, @what. I think writing is about creation rather than consumption. Write what you like, even if nobody else is doing it. (I think that's unlikely, but...) If you write something unique, and write it well, then you'll have readers. No, wait. Who cares about having readers? You'll be a different person after writing a novel, regardless of whether it's ever read.
Comment: "But for those people this question is nonsensical" - As one of *those* people, I disagree.  I do experience doubt about my writing style and do care about its quality and accessibility even if few will read it.
Comment: Mark, I agree with your general approach, but I think your bottom line is problematic. Not everything _has_ been done before (and writers don't always know it if it has). "Can I write a vampire story, but the vampires glitter?" "Can I write a survival story, but on Mars?" "Can I write a movie where all the scenes are in reverse order?" Innovation _just_ in order to innovate is usually a drag, but _good_ innovation on a firm base can be great. That's a long way from saying "you can't do those things" or "nobody will like it."
Comment: @Kevin but you are presumably writing as if it were to be read by someone. If not, what could you have doubts about? Why would you care about its accessibility if it were not written to be accessed by a reader? You may not think it ever will be, but if you are writing as if it were to be read, then you are writing for a reader.
Comment: I choose to care about accessibility, because I don't want to produce Avant garde nonsense, and for my own consumption 6+ months in the future.
Comment: Yes, some people write purely for their own enjoyment of writing. But for those people the question is nonsensical. If you are not writing for a reader, you can write in binary coded unicode using only ones and zeros and be happy as a clam. The question only makes sense if it is about writing for a reader.
Comment: But is any other art constrained by the requirement of having an audience? If I paint hundreds of paintings and nobody sees them, am I not a painter? If I create dozens of sculptures but destroy each one when I'm done, am I not a sculptor? Why is writing the only art which requires interaction? or publication?
Comment: @LaurenIpsum, all art requires the _intention_ to communicate. An act of communication may never be received, but if the act is never intended to be received, it is a different act. I'm not saying it is an invalid way to amuse yourself if that is what floats your boat. But without the intent to communicate, to share, it is a qualitatively different act.
Comment: There's a typo:  -->"In neither needs "
Comment: @MarkBaker If I could, I would heap gold onto your comment in which you say that *writing* is communication and contrast it with *masturbation*.
Comment: (Although I will grant that the people likely to do well writing innovative things, are probably not the people coming to a Q&A site and asking "So, ummm, I allowed to do this thing I've thought of?" :P )
Comment: @Standback, I think every story is unique. There is infinite room for innovation in creating particular stories. But I think there is little if any room for useful innovation in the shape of story itself, or in the modes of storytelling. New stories, yes. New types or stories or new ways of telling, no. Far too many young writers, it seems to me, spend too much of their time trying to innovate in type and telling when they should be focussing on creating new stories in all their specific grittiness.
Comment: @MarkBaker : I generally agree, and agree even more when it comes to new writers :D But, since this is effectively a meta-question, and it's likely to get linked for all sorts of values of this-and-that, maybe edit to clarify the distinction -- innovation in content, vs. innovation in form, shape, mode?
Answer: You can write anything you please.
Comment: I'd add that you can, but it may not accomplish [goal].
Comment: [Heart-felt defense of the site's specs] followed by [admits Stack Exchange has issues by an attempt to appeal to a specific, narrow Q&A mindset]. [Barely-relevant joke goes here]
Comment: This answer, due to it's length, would be better suited as a comment. Would you be interested in [doing thing X] that would result in [improvement Y]?
Comment: @NeilFein I believe the answer to my question is "yes". I only expanded on that because SE does not allow three-letter answers.
Answer: I'd be surprised if it was impossible to write something.
You've just got to write it. See how it goes.
Answer: Sure, why not? Get it on paper, kick it around a bit, and then hand it off to an editor to see if it worked.
Comment: As other answers mention, there's no inherent link between writting a novel and having it published.
Comment: @PierreArlaud Um, yes? Kevin notes above that he would do just that. If you're writing for yourself, why wouldn't you want to learn how to improve your work for yourself? Why settle for crap?
Comment: @PierreArlaud You can still edit a work for yourself. It's nearly impossible to see all the flaws in your own writing; you almost have to have an outside perspective. That's what an editor is for.
Comment: I just meant that being published is not a goal in itself. You might write a book for your kids or just as a way to develop yourself, in which case the answer is "write whatever you want". There are no rules and being published isn't one.
Comment: @PierreArlaud I agree... so why did you add a comment about being published to my answer, which doesn't mention being published?
Comment: Ha, so you mean handing it to an editor just to get an opinion? Now that's interesting!
Answer: You may write a novel.  I'm not sure if you can or will though. :)
If you do write a novel -- a fiction of an acceptable length to be considered a novel -- no one truly has the authority to tell you it is wrong or bad.
For a novel is anything fiction of a certain length that someone considers a novel.  So if you'll simply consider it a novel yourself, you will be successful.
And, if it's really out there but a publisher picks it up then you can say you've created art.
Like House of Leaves by Mark Danielewski - amazon link :)


Is it possible to synthesize speech?

Question: All of my Google research gives me results for text-to-speech. This is not what I am looking for. Instead, I am wondering if it is possible to create a "voice" (or recognizable speech) from scratch with no recordings. What is the difference between voice waves and noise waves?
Comment: I've seen this question and got curious, what is the difference of what you look for from a text-to-speech software? that is, how would you tell the system which words or sounds to produce without some text-based encoding?
Answer: "Is it possible to create a voice from scratch with no recordings."
One system I was looking at is from the 1970's called VOSIM. (Just wrote a Java version of the basic algorithm about a month ago. It only makes simple tones, not words.) Yes, it sounds very robotic and artificial. But I think it was (is) possible to make recognizable words, especially with later iterations or with other such systems.
"What is the difference between voice waves and noise waves?"
The closest that voices come to "noise" (if taken to mean random sound waves) is the production of sibilants and fricatives (some of the consonants, like "s" or "f"). A big part of what makes them different is that these sounds are run through a resonating system (the throat and mouth) that amplifies certain frequency areas. You can learn more about this by researching "vocal formants" which also are a key to the forming of the particular timbres that are used to identify vowels.
An artificial system has to control for the timing of many components, not just the pitch of the spoken tones, but the formant transitions as well as amplitude transitions arising from plosives and stops. Getting synthesizers to do all this on the fly is quite a task--having samples is a big processing help and sounds better.
There is a good, downloadable (free) book that talks about the basics contours of speech recognition. You might want to check out. It's called "The Engineer and Scientist's Guide to Digital Signal Processing" by Steven Smith. The relevant section is in chapter 22. It may be a little dated but seems to me to be holding up well (anticipating neural net solutions). "Recognition" may be the opposite of "simulation," but if you are trying to recognize something, you need to be able to create some sort of model. And a model that can be used to match a sound can also be the used as a source for a sound, right? So, many of the issues discussed in the chapter are pertinent and should help you get a better understanding.
Comment: Thanks, Phil! I'll have to read that book in my spare time! :)
Answer: Oscillators in synths are used to create some vowels or even choir pads but speach synthesis still relies on pre-recorded samples due to the sheer intricacy of voice patterns.
I would imagine granular synthesis could handle parts of a sentence yet connecting those to have meaning would still be a challenge.
There's a lot of research going on at the moment on this topic, most notable is the WaveNet that would add mood and transients in text to speech algorithms:
https://deepmind.com/blog/wavenet-generative-model-raw-audio/
Comment: Your first sentence is not actually correct Dalv - synthesis that hasn't used samples has been around for ages. It's just nowhere near as good :-)
Comment: The wavenet-generative link is scary-good.
Answer: Speech synthesis has existed for over 30 years. I had a computer that did it from scratch in the early eighties. Back then it did sound very robotic. As Dalv pointed out, the current research is far improved from those days, so most variants sound much more realistic.

Is it possible to synthesize speech?


How to avoid a loud, embarrassing sneeze?

Question: How do I prevent myself from sneezing loudly? Apparently my loud, embarrassing sneeze wakes up neighbors of my presence in the building.
Comment: I live with someone who uses full vocal cords to yell HOOOO as part of every ac-HOOO sneeze, and cannot prevent that from happening. The OP may do something similar. (More details in the question would be helpful, including what has been tried.)
Comment: @DangerZone I have been described to *sneeze like a rocket*. If my feet are on the ground while I'm sitting in one of those wheeled office chairs and I sneeze, I'll send myself flying through the room with spin from the force.
Answer: This might take some training, as it is counter-intuitive, but it works like magic for me:
As soon as you feel the urge to sneeze building up, exhale completely. You might have to try a few times to find out how early in advance you have to start, and how fast or slowly you have to exhale. The idea is to have exhaled completely at the "point of no return", but also that you don't suffer.
In the end, if there is not much air inside you to burst out explosively, it will not make a significant noise. Good luck!
Answer: Personally, I hold in every sneeze. I can't say I recommend it, as this article points out: "The risk of a hearing loss injury due to holding a sneeze is low. However, it is not impossible."
Wiki's page on sneezing does a good job explaining what happens in a sneeze. Basically, nose hairs send a signal to the brain, which starts a massive response in the upper body's organs to expand and then contract the chest violently. Since this signal is sent through the nerves, there are lots of ways to try to stop the sneeze completely.
For example, some ideas from this wikiHow page are rubbing your nose, pinching the bridge of your nose, pinching the tip of your nose, pulling on your ear, etc. These suggestions come from the idea of sending another signal down the nerve and thereby sort of messing with your brain.
Answer: Simple trick which always works is to press right below your nose. In most cases you will completely avoid sneezing. Good luck!
Answer: If you can't avoid the sneezing, then sneeze into the crook of your arm.
When wearing a long-sleeved, preferably soft and thick piece of clothing, this will muffle the sneeze to a good degree. This solution has the advantage that it's available in time for every sneeze. And in general, it is microbiologically much safer than sneezing into your hand – as in, potential germs will not spread with the next handshake, touching things etc..
Answer: Sneeze into a folded towel or pillow will muffle the sound.
Answer: While the sensation is building up, try to force the sneeze out, with all your willpower. It sounds weird but actually works.
Anytime I was on the verge of sneezing and tried to force it out and get it over with, the need to sneeze subsided. Using that actively requires a little bit more willpower, since you're trying to build up the intention to do something you actually don't want to while trying to avoid doing it involuntarily.
Make sure to blow your nose afterwards, the cause of irritation will probably still be somewhere in your sinuses.
Answer: If you're awake when you sneeze, trying to hold your breath or plug your nose before the sneeze comes out makes the sneeze a lot less explosive and therefore quieter. Keeping your mouth closed will likely help as well.
Comment: Just to note: holding a sneeze can be dangerous.


How to find the folder of a salesforce report?

Question: Is there any relationship between salesforce Reports and Folder objects, to determine the content of the folder or find the residing folder of a particular report ?
Answer: The Report object does not have a FolderId field like Dashboard, Document and EmailTemplate objects. But as you can see from this their does exist a child relationship between Folder and Report, which is in fact determined by the OwnerId of the Report.
Thus once you know the folder Id you can query for reports that are contained within it.
SELECT Id, DeveloperName,Name,Type FROM Folder
  WHERE Name = 'My Test Folder' And
              Type = 'Report'

Then query by OwernId with the Folder Id returned e.g.
SELECT Description,DeveloperName FROM Report WHERE OwnerId = '00lG0000000TwG5IAK'

Answer: Reports can be created in public folders or in personal folders. It all depends on whether you want to make them available for others to use. For more details on the subject, you might want to look at Using the Reports Tab.
Answer: you could create a custom report type on report object and by editing its layout, using folder lookup relationship pull any folder fields needed. Creating a report using this report type will show folder details along with report's.
Answer: If you don't need to access Reports or Folders in code then you can simply use the 'Reports' administrative Report Type, to view all public reports and any in your My Personal Reports folder, along with the folders that they're contained in.
You'll need the 'View Setup and Configuration' permission in order to access this Report Type see here.


How can I achieve this sound?

Question: I would like to achieve the main neuro sound (1:07 in the video) of this track.
Any tips or tutorials?
Best,
Comment: I don't know what 'neuro' means, but there are two bass sounds happening, one sub sound, and one gritt sound; the sub is in like a 6/8 wobble and the gritt is in an 8/8 cycle, both start on the first off beat. Which do you mean?
Comment: neuro is a type of sound really organic and expressive used in neurofunk style.
Answer: That sounds like a relatively simple wobble and I'm sure there are a massive amount of different techniques for achieving this. I would start with a basic approach, that being the somewhat archaic technique of getting a "gabber" sound by distorting a long-tail 808 kick drum (I believe that is what wobbly baselines gradually evolved from).
More particulary - to achieve the sound you are going for, I would start with either an 808 bass sample, or a clean sine-wave synth patch tuned down a couple octaves to get a sub-bass sound then write the baseline. Next I would to add pitch and frequency modulation to my baseline then map both to a midi-knob or simply automate it. I would go easy on the pitch, maybe just a few semitones, but the modulation of the frequency and the pitch sound like they are in the same time. All of that would go through a distortion effect: this could be overdrive, gain, or saturation, or if you want it to sound more like a disgruntled robot voice you could even use a bit-crusher and down sample it.
Next I would make a copy of that. In order for it to sound good, the sub-bass needs to be separated from the distortion. For the copy of the baseline, turn off the distortion effect and cut off the frequencies that extend beyond the sub bass, usually around 60HZ. Also I would find a way to make the output of the sub bass mono so you only hear it in the center.
As for the original track with the distortion, do the opposite and roll off everything below 60HZ.
Ultimately - to keep the kick drum and the sub bass from washing each other out, I would throw a compressor on the track with the sub bass and run a side chain from the kick drum.
Comment: Any precise settings? Thx
Comment: Any settings will most likely be particular to the devices/FX you are using. Anything more precise than that would be along the lines of writing "that component of the song," not "how to achieve the sound." A good producer doesn't go out and bring a pre-tailored baseline to a composition. The baseline is created within the song.
Answer: The bass sound under there is a slight hoover effect, the bass oscillators are slightly detuned and one of them is rough like a square wave or something with very wide frequencies...
they take that sound and put the filter on an LFO's and have other filters that are static and doing a bass cut with them... there is probably a slight postprocessing effect to enrich it even further and you can choose from any kind of slight delay echo overdrive of the millions available to fatten up a bit further.
the filters are very complex and you want get that mix in a hurry, but you can put the sound through a spectroscope and i GUARANTEE you that you will have a solid grasp of the frequencies that are being let through and the LFO frequencies. You will have trouble to find a synthesizer with that powerful filters, it's not a cheap one. there are at least 4 filters on that at the same time, but synths usually give you a mix of 3-10 filters all on the same control which are used as a single filter, so you need at least 2-3 complex ones for that effect.
the secret to complex sound is hoover oscillation large and small i.e. detune. detune makes an entire recording sound lofi oldschool natural rich organic non robotic complex characterful and interesting. not alot of synths give you control of detune cos nobody knows that.

How can I achieve this sound?


Why is Penny less concerned about the "check engine" light?

Question: On many occasions in The Big Bang Theory we have seen Penny being questioned about the "check engine" light, especially by Sheldon Cooper and even by Beverly Hofstadter. So is there any significance or just Penny's carelessness?
Comment: @panther you spelt Wine wrong.
Comment: May be she is just careless and spends her salary in other things like makeup & dresses. I believe it only reason.
Comment: @cde or shoes. She buys a lot of shoes.
Comment: OT, but this question made me think of the following conversation from "Last Man Standing":  Dad: "So Mandy, now you know that the 'check engine'-light doesn't just mean for you to check that you *have* an engine."  Daughter: "I already knew I had an engine, it was where the smoke was comming from." (or something along those lines)
Answer: The check engine light is being used as an indicator of the relative difference in general concern by Penny versus Sheldon or Beverly.
The check engine light in modern vehicles quite often indicates an issue with the emissions control system, although as commenters have noted it can cover a wide variety of vehicle faults (including those unrelated to the engine).  Often these underlying issues pose no immediate danger to the mechanical function of the car, the initial symptoms of emissions issues being increased environmentally-harmful emissions and lower fuel economy.
Thus, many people ignore the check engine light, either after checking it once and finding out that the underlying issue is emissions-related or otherwise not immediately harmful, or in some cases never checking it at all.  However, there is always a chance that the problem is one that may quickly damage the vehicle, and the only way to know for sure is to have the error code checked by a mechanic (or checking it yourself if you have the specialized equipment).  In addition, a person who cares deeply about their environmental impact would want to fix any underlying emissions problem, not to mention the potential for long term damage if the light is consistently ignored.
Thus, response to the check engine light can show how careful a person is along a continuum from most careless to most careful:

completely ignoring it from the get go
having it checked the first time it is lit but assuming things are fine on subsequent lights
having it checked it every time it goes on
not operating the vehicle until the underlying cause is solved

Sheldon and Beverly are both of the sort that is very concerned with minutiae, and Sheldon in particular has shown concern for potential issues of low probability but high potential impact.  Both are detail-oriented and meticulous.  Penny, conversely, lives a somewhat oblivious existence, relying on her ability to respond to situations rather than on extensive planning, care, or forethought.  Their responses to the check engine light are indicative of these personality traits.
Comment: The check engine light, also known more correctly as the Malfunction Indicator Light actually covers far more than the engine and emissions systems in modern cars, such as the brakes (P0504), air conditioning (P0535), security system (P0513), steering (P0635) and transmission (P0700). See the OBDII standard for a complete list, and many manufacturers will add their own proprietary codes as well, especially on the high end brands. And besides checking it yourself, or sending it to a mechanic, some big box autoparts stores like AutoZone will check it for free and tell you what codes are stored.
Comment: @mattburnett Quite true.  Someone appears to have deleted my previous comment re: coverage of the complete universe of technical details on the light, but the purpose in this answer is to cover it in regards to its use as a narrative device, rather than to provide content better suited for the Mechanics beta stack exchange.  As noted in the answer it can be a variety of underlying causes.
Comment: What's not mentioned is that the show is set in California, and Pasedena of Los Angeles county is subject to [Smog Checks](https://www.dmv.ca.gov/portal/dmv/?1dmy&urile=wcm:path:/dmv_content_en/dmv/vr/smogfaq). So, not resolving a Check Engine indicator in Penny's case could lead her to fail a smog check and possibly lose the ability to legally drive her car (until it's resolved).
Comment: @CreationEdge My guess is that staying on top of smog checks may fall under the same level of care she has for the CEL ;)
Comment: Yes, and also is more reason for someone like Sheldon to be on top of it, because it's not only good for maintenance but the law.
Answer: It is also implied, deliberately or otherwise, that she doesn't understand what the light is for. In Series 2 Episode 14 – The Financial Permeability, there is a conversation between Penny and Sheldon where the engine does inevitably break:

Sheldon: If you recall, I pointed out the "check engine" light to you several months ago.
Penny: Well the "check engine" light is fine. It's still blinking away. It's the stupid engine that stopped working. It cost me like twelve hundred dollars to fix it.

Quote Source
Comment: This reads to me like a simple joke, not an indicator that Penny didn't know what the light meant.
Comment: @Lilienthal have you not met Penny?
Comment: @Lilienthal I was looking for a video of the quote, because although it reads like a joke it's played very deadpan so doesn't sound like one (although obviously it is there for laughs)
Comment: @Lilienthal, well, maybe, but if the light is on even after fixing the engine, then what does it indicate?
Comment: It is definitely deadpan, but I always assumed like you that it was a joke at the time and not implying she didn't know what it meant.  Given Sheldon's (and Amy's and Beverly's) repeated comments about it, it strains credulity that she could not in a general sense know what it means.  (It's also at odds with her Nebraska Corn Fed personality.  She almost certainly would have had some knowledge of car repair.)
Comment: @cde I'm aware of her moments of brilliance, I was just willing to give her the benefit of the doubt and assume that the writers were going for situational humor. Though that's based on the text, if it was played completely deadpan then he's probably right.
Comment: It is no way implying that she don't know. Its just she don't care
Answer: It should also be noted that Penny is a waitress and doesn't really make much, for regularly maintaining a costly possession like a car.
So, she doesn't care about the car's condition unless and until the problem is a major, like the one pointed out by @MatthewSteeples.  In Penny's words:

Sheldon: If you recall, I pointed out the "check engine" light to you
  several months ago.
Penny: Well the "check engine" light is fine. It's still blinking
  away. It's the stupid engine that stopped working. It cost me like
  twelve hundred dollars to fix it.

So, a sensible inference to make is that even if she knows what the light is or, she can't/doesn't really care to repair it as she cannot afford minutiae servicing (which can cost a lot for a car).
In addition, Penny represents most (American) common people. And most people don't really care about the environment unless it is directly spoiling our health or is costing us a lot. Thus the reluctance of Penny towards servicing the problem.


mod _python and Python 2.6

Question: Is there anyway of getting mod python to run on the latest version of python, or do i have to downgrade my python installation to 2.5.5?
Comment: user crosspost on SO: http://stackoverflow.com/questions/2730671/making-python-run-on-my-webserver
Answer: This doesn't answer your question, but mod_wsgi has pretty much superseded mod_python. If possible, I'd consider using it http://code.google.com/p/modwsgi/
Answer: You need to build it using python 2.6's development libraries afaik, but a much better solution is to use FastCGI/SCGI, which will let you run not only multiple versions of python on apache, but also multiple versions of php, ruby, and other webapps, even if you decide you want to move to lighttpd, nginx, or some other webserver too.  It's not without issues, but the (relatively) standardised interface that FastCGI provides is seriously underrated.  Getting started with mod_fcgid on apache isn't much trouble at all.
Answer: You didn't say which operating system you're running but I see that under Debian it's not supported under Python 2.6 or higher, even in the testing or unstable version.
Mod_python is pretty much obsolete.  Most people have switched to mod_wsgi and are building Python apps using wsgi compatible frameworks such as Django, Pylons etc.
http://code.google.com/p/modwsgi/
Answer: That you are even asking makes me think you are using Windows.
Windows binaries for mod_python are only available up to Python 2.5. There are no binaries for mod_python for Python 2.6 and Python 3.X is not supported at all by mod_python. You could build mod_python yourself from source code, but you will need Visual Studio 2008.
On most UNIX systems which provide binary packages, you should have no issues finding mod_python for Python 2.6.

mod _python and Python 2.6


Joseph Smith purpose of polygamy

Question: Why did Joseph Smith condone, or perhaps even encourage polygamy?  What scriptures, if any, support this practice?
Comment: I have edited the question completely, in hopes of keeping the original intent of the question, while making it answerable.  I hope I was faithful to the OP's intent, although the original seemed to be bringing "no other gods" into the question, and I'm not sure how that was meant to tie into the question about polygamy... so please feel free to re-edit if I missed something in my rewrite.
Answer: There was polygamy, or plural wives, in the Old Testament.
Starting with the (NRSV) Bible.

Sarai gave Hagar to Abram as his wife, Genesis 16:1–11

Jacob received Leah and Rachel and their handmaidens as wives, Genesis 29:21–28, Genesis 30:4, 9, 26.

If a man take another wife, he shall not diminish the first wife's possessions, Exodus 21:10

David and his two wives went up to Hebron, 2 Samuel 2:1–2

In the Book of Mormon, the book of Jacob, Jacob explains to the Nephites how God sees plural wives. (Jacob 2:27-30)

27 Wherefore, my brethren, hear me, and hearken to the word of the Lord: For there shall not any man among you have save it be one wife; and concubines he shall have none;
28 For I, the Lord God, delight in the chastity of women. And whoredoms are an abomination before me; thus saith the Lord of Hosts.
29 Wherefore, this people shall keep my commandments, saith the Lord of Hosts, or cursed be the land for their sakes.
30 For if I will, saith the Lord of Hosts, raise up seed unto me, I will command my people; otherwise they shall hearken unto these things.

So God has to command plural marriage by revelation.
Unfortunately for Joseph Smith, God revealed that he wanted all things restored, including polygamy.  This revelation was recorded 12 July 1843, and is known in the Doctrine and Covenants as revelation 132.

37 Abraham received concubines, and they bore him children; and it was accounted unto him for righteousness, because they were given unto him, and he abode in my law; as Isaac also and Jacob did none other things than that which they were commanded; and because they did none other things than that which they were commanded, they have entered into their exaltation, according to the promises, and sit upon thrones, and are not angels but are gods.
38 David also received many wives and concubines, and also Solomon and Moses my servants, as also many others of my servants, from the beginning of creation until this time; and in nothing did they sin save in those things which they received not of me.
39 David's wives and concubines were given unto him of me, by the hand of Nathan, my servant, and others of the prophets who had the keys of this power; and in none of these things did he sin against me save in the case of Uriah and his wife; and, therefore he hath fallen from his exaltation, and received his portion; and he shall not inherit them out of the world, for I gave them unto another, saith the Lord.
40 I am the Lord thy God, and I gave unto thee, my servant Joseph, an appointment, and restore all things. Ask what ye will, and it shall be given unto you according to my word.

Poor Joseph.  God commanded him to restore all things.  He felt obliged to marry 34 other women.
Comment: Are you saying that: "For there shall not any man among you have save it be one wife" means men should have more than one wife?  It's a bit unclear, but I would have read it as requiring monogamous marriages.  Or am I misunderstanding some sarcasm here?
Comment: @JonEricson: It took me a minute to find your reference.  Jacob tells the Nephites that God forbids polygamy, except when he specifically commands it.  That polygamy command came to Joseph Smith in revelation 132.  The comments about Joseph Smith's reluctance to engage in polygamy were somewhat sarcastic.
Comment: @JonEricson, yes v. 27 states that monogamy is the standing law before God.  It's v. 30 that states that God will sometimes command something other than monogamy.
Answer: According to the LDS Church, of which Joseph Smith was the founder, "Latter-day Saints do not understand all of God's purposes for instituting, through His prophets, the practice of plural marriage during the 19th century. The Book of Mormon identifies one reason for God to command it: to increase the number of children born in the gospel covenant in order to "raise up seed unto [the Lord]" (Jacob 2:30)." Plural Marriage and Families in Early Utah - LDS.org

Joseph Smith purpose of polygamy


Acer Aspire-R7 WiFi

Question: Will Ubuntu ever support the Acer Aspire-R7? It uses a custom Broadcom chipset. I even tried using an external USB 'EnGenius Wireless N', but the driver crashes. I give up at this point. I don't have an ethernet port and don't want to switch to another Linux distribution. Does the Beta support this chipset or is Ubuntu and Acer R7 a deadend?
Comment: Please edit your question to add details of your wireless device from the terminal: lspci -nn | grep 0280
Comment: This has been handled in depth at [http://askubuntu.com/questions/55868/how-to-install-broadcom-wireless-drivers-bcm43xx][1]

  [1]: http://askubuntu.com/questions/55868/how-to-install-broadcom-wireless-drivers-bcm43xx
Answer: Actually I really don't know what is your pc's properties. But my laptop has Broadcom wifi adapter. When I installed ubuntu my wifi card wasn't working, i connect it to internet with an ethernet cable than let it to install additional devices which Broadcom listed in it. After installation it works like a charm. If not, you can manually install broadcom-sta-drivers to make it work.
Have a nice day..

Acer Aspire-R7 WiFi


downloading files into Zune

Question: I got my hand into a old Zune. It does seem functional. I can p[lay songs present in it. But I am just not able to download any files into the player. The songs are my own and I don't want to go through the marketplace. Any suggestions on how to go about to setting up downloading these files into the zune?
Comment: Any errors while downloading the files?
Comment: And also make sure your Zune's firmware is updated to latest version.
Comment: @ahmed I can copy files from the Zune to my computer but not the other way around.
Answer: The free Zune software is a very nice music library / player.  I've never owned a Zune player but I have enjoyed using the software for years.  It subscribes to and plays video and audio podcasts nicely as well.  My favorite feature is the very handsome "now playing" graphic display in which the software gets images of the artist from the internet and manipulates them into a colorful animated display appropriate to each song as it plays.  Quite cool and great for a party situation!
Answer: The simplest way should be to use the Zune Software from Microsoft. I've always used that and it's never given me any trouble. Granted, I have a Zune HD, but I'm pretty sure it works with older Zunes.
Answer: If you are using Windows (XP to 7) you can install the Zune software from www.zune.net.
If you are using a Mac and you have a Zune HD, try http://www.microsoft.com/windowsphone/en-us/apps/mac-connector.aspx.  This may work for older Zune devices.
Once you install the software, you may need to update your device firmware.  Do this - as the software only talks to devices running the latest firmware.
Once this is done you should be able to add any non-DRM music to your "collection" and from then sync to your device.  You can either configure your device to automatically sync, or do manual sync.  in the latter mode, you drag just the artists/albums/songs to the device icon in the lower left.

downloading files into Zune


When to use the different types of Encryption / hash algorithm?

Question: I'm studying for CISSP and know they will ask what type of encryption to use in different situations. Does such a list exist or is there a general rule of thumb to use?
Comment: Look at the difference between stream and block ciphers. When or how often do you need to re-key?
Comment: Well there is list of ciphers, hashes, also prngs, as well the PKI certificates, so in every situation you need to design something which is best suited, but this largely depends on the situation.
Answer: I think in general you'll need to understand the difference between symmetric and asymmetric encryption.  Symmetric algorithms are faster and stronger per bit of key length than asymmetric algorithms.  But symmetric algorithms require a pre-shared key and asymmetric algorithms do not.  So, in situations where strength and speed is required, and securely pre-sharing a key is possible, you would use symmetric ciphers like AES.
In practice, cryptographic hashes, symmetric and asymmetric encryption are combined to provide a more complete solution.  For example, asymmetric encryption can be used to exchange the keys for symmetric encryption.  This is how Secure Sockets Layer (SSL) works.
Answer: The general reasoning looks like this:
We have some sensitive data which must be transformed to preserve its confidentiality. Does it needs to be transformed back ? If no, then this is a case for hashing, not encryption (as in "password storage": you do not want to get the password back, you just want to verify that a given password matches what was stored). Password hashing is sometimes called "encryption" (that's wrong, but widespread).
Assuming we need to do actual encryption, then will the people doing the encryption be the same entity (morally) than the people doing the decryption ? If both are the same entity (e.g. you encrypt a file so that you can retrieve it later on), then that's symmetric encryption (encryption and decryption use the same key). Otherwise, that's asymmetric encryption (typical case: encrypted emails: encryption by the sender, decryption by the recipient, who is somebody else).
If doing symmetric encryption, then use AES -- but do it in a proper mode such as EAX, which ensures confidentiality and integrity. There are other encryption algorithms, some of which providing better performance in some situations, but it takes some creative engineering to find a situation where AES speed is not more than adequate. Don't pollute security design with unsubstantiated worries about performance.
If doing asymmetric encryption, then you will probably need to use hybrid encryption: you asymmetrically encrypt a random key (a bunch of bytes), which you then use for symmetric encryption over the actual data. Asymmetric encryption algorithms (such as RSA) don't handle bulk data; some of them do not actually let you choose the data which you encrypt (these are key exchange algorithms like Diffie-Hellman).
And, of course, don't do it yourself. Cryptographic algorithms are sensitive beasts; it is easy to get it wrong when assembling them into protocols. You should rely on existing protocols as much as possible. For instance, you do not encrypt an email; you use S/MIME or OpenPGP, which will take care of applying the encryption in an appropriate manner.
Comment: Some day, I will run into the original question asker, and he will tell me that he insured both confidentiality and integrity by using EAX. I'll ask him if he ever studied cryptography, and he will say "no." I don't think this type of high-level crash-course answer on such a hazard-prone topic serves anyone.
Answer: You're asking how you know what "type of encryption" to apply in a given situation. This could mean one of two things.
If you want to know how to apply cryptography as an engineer, you need a thorough knowledge of various algorithms, protocols, and attacks. If that's your goal, he Handbook of Applied Cryptography (HAC) is a unique and crucial resource. This is a technical book intended for readers with some computer science background, and its coverage of the area is unmatched in breadth and detail. However it is also somewhat out of date, as books on cryptography tend to be. On that note, you would also need to catch up by surveying cryptography-related journals and works on elliptic curve cryptography (ECC) in the intervening years since its publication, and continue to follow such things in the future.
Since you're studying for a CISSP, however, I suspect that you want a higher-level view. Be warned that pursuing this path will not qualify you to apply cryptography on an engineering level. It will support you in high-level specification of products and technologies, which is what CISSP's tend to do — but you will need to acquire (or work with someone who has) deeper knowledge to engineer, verify, and test the security of your applied crypto. If this is your goal, there are all kinds of CISSP study guides, and also Bruce Schneier's famously accessible Applied Cryptography which gives a decent survey of algorithms and their particular applications but little in the way of theory. There is also Cryptography Engineering, which is a clasically Schneier-style reduction of HAC's outline into a book that reads like an InfoWorld article from start to finish.
I would be remiss not to give the usual warning about snake oil crypto. Choose products from highly-established open-source projects or vendors that specialize in security and cryptography. Engineering cryptography is not a common skill, or something to be dabbled in. Even the experts don't often get it right.


Multiple download sites for verification

Question: I want to download Tails and verify by comparing multiple downloads from different sites. Can anyone point me to a list of these sites please? If I go to tor project.org there is just one download button. thanks in advance.
Answer: Your options are either to download Tails via:

bit-torrent;
HTTPS from a mirror.

However, the way that the official Tails mirrors work is to actually act as virtual hosts with the main site pointing to them, meaning there is only one button, rather than a list of places from which you can download.
I'm assuming the reason for this is to prevent Bad People setting up their own private mirrors and serving compromised versions of Tails to users who don't know to download it from the official site, and therefore are ignorant to the official advice about authenticating the ISO...
...Therefore, if you're worried about the authenticity of anything you download from the official site, see if the details on verifying the ISO, and the more detailed page on trusting the signing key, set you mind at rest.
Whether or not you can trust this advice has been discussed in the past.
Comment: Thank you both for taking the time to answer my question. I'll probably go for a BitTorrent download.
Answer: Use a bittorrent download - it will be verified by alot of people.