query: What extra information might be obtained from the next highest bids in an order book?

positive: The Level 2 data is simply showing the depth of the market. If I am trading shares with my broker I have the option of viewing only the top 10 bid/ask prices in the depth or all of the data (which sometimes can be a very long list). With another broker I get the top ten bid and ask prices and how many orders are available for each price level, or I have the option of listing each order separately for each price level (in order of when the order was placed). I get the same kind of data if trading options. I do not know about futures because I don't trade them. Simply this data may be important to a trader because it may give an indication of whether there are more buyers or sellers in the market, which in turn may (but not always) give an indication of which way the market may be moving. As an example the price depth below shows WBC before market open with sellers outweighing the buyers in both numbers and volume.  This gives an indication that prices may drop when the market opens. Of course there could be some good news coming out prior to market open or just after, causing a flood of buyers into the market and sellers to cancel their orders. This would change everything around with more buyers than sellers and indicate that prices may now be going up. The market depth is an important aspect to look at before putting an order in, as it can give an indication of which way the market is moving, especially in a very liquid security or market.

positive: My broker collates the order book by price and marketplace, displaying the number of shares available at each level, sorted as in Victor's screencap. You can glean information from not just a snapshot of the order book but also by watching how it changes over time. Although it's not always a complete picture -- many brokers hold limit orders internally until the market is close, at which point they'll route to an exchange or trade internally. And of course skilled market participants know that there's people out there looking to glean information from the order book and will act to confuse the picture. The order book can show you: Combined with a list of trades (price & size, and whether it was a buy or sell), you can get a much more complete picture of what's going on with a stock than by looking at charts alone.

negative: In order to see whether you can buy or sell some given quantity of a stock at the current bid price, you need a counterparty (a buyer) who is willing to buy the number of stocks you are wishing to offload. To see whether such a counterparty exists, you can look at the stock's order book, or level two feed. The order book shows all the people who have placed buy or sell orders, the price they are willing to pay, and the quantity they demand at that price. Here is the order book from earlier this morning for the British pharmaceutical company, GlaxoSmithKline PLC.  Let's start by looking at the left-hand blue part of the book, beneath the yellow strip. This is called the Buy side. The book is sorted with the highest price at the top, because this is the best price that a seller can presently obtain. If several buyers bid at the same price, then the oldest entry on the book takes precedence. You can see we have five buyers each willing to pay 1543.0 p (that's 1543 British pence, or £15.43) per share. Therefore the current bid price for this instrument is 1543.0. The first buyer wants 175 shares, the next, 300, and so on. The total volume that is demanded at 1543.0p is 2435 shares. This information is summarized on the yellow strip: 5 buyers, total volume of 2435, at 1543.0. These are all buyers who want to buy right now and the exchange will make the trade happen immediately if you put in a sell order for 1543.0 p or less. If you want to sell 2435 shares or fewer, you are good to go. The important thing to note is that once you sell these bidders a total of 2435 shares, then their orders are fulfilled and they will be removed from the order book. At this point, the next bidder is promoted up the book; but his price is 1542.5, 0.5 p lower than before. Absent any further changes to the order book, the bid price will decrease to 1542.5 p. This makes sense because you are selling a lot of shares so you'd expect the market price to be depressed. This information will be disseminated to the level one feed and the level one graph of the stock price will be updated. Thus if you have more than 2435 shares to sell, you cannot expect to execute your order at the bid price in one go. Of course, the more shares you are trying to get rid of, the further down the buy side you will have to go. In reality for a highly liquid stock as this, the order book receives many amendments per second and it is unlikely that your trade would make much difference. On the right hand side of the display you can see the recent trades: these are the times the trades were done (or notified to the exchange), the price of the trade, the volume and the trade type (AT means automatic trade).  GlaxoSmithKline is a highly liquid stock with many willing buyers and sellers. But some stocks are less liquid. In order to enable traders to find a counterparty at short notice, exchanges often require less liquid stocks to have market makers. A market maker places buy and sell orders simultaneously, with a spread between the two prices so that they can profit from each transaction. For instance Diurnal Group PLC has had no trades today and no quotes. It has a more complicated order book, enabling both ordinary buyers and sellers to list if they wish, but market makers are separated out at the top. Here you can see that three market makers are providing liquidity on this stock, Peel Hunt (PEEL), Numis (NUMS) and Winterflood (WINS). They have a very unpalatable spread of over 5% between their bid and offer prices. Further in each case the sum total that they are willing to trade is 3000 shares. If you have more than three thousand Dirunal Group shares to sell, you would have to wait for the market makers to come back with a new quote after you'd sold the first 3000.

negative: "I think for this a picture is worth a thousand words.  This is a ""depth chart"" that I pulled from google images, specifically because it doesn't name any security.  On the left you have all of the ""bids"" to buy this security, on the right you have the ""asks"" to sell the security.  In the middle you have the bid/ask spread, this is the space between the highest bid and the lowest ask.  As you can see you are free to place you order to the market to buy for 232, and someone else is free to place their order to the market to sell for 234.  When the bid and the ask match there's a transaction for the maximum number of available shares.  Alternatively, someone can place a market order to buy or sell and they'll just take the current market price. Retail investors don't really get access to this kind of chart from their brokers because for the most part the information isn't terribly relevant at the retail level."

negative: "Without knowing what the balances are, I associate ""uncomfortable"" with high, as in tens of thousands.   What I would do: is 1) cut up the cards and stop using them, and 2) have some balance transfer offers in hand the next time you call to negotiate with the companies.  Essentially, you will have to convince them that they will have to explain one of two things to their boss: why they lowered your rate or why you left. They can collect less interest from you or no interest from you.  It's up to them.  If they don't offer you something that's in the ballpark of your balance transfer offer, then bid them goodbye and complete the balance transfer. As far as paying them off, the top two modes of repayment are lowest balance first (aka snowball) or high interest rate first.  Both methods are similar in that you pay minimums on all but the method's focus point.  Whether it is lowest balance or highest interest rate, you pay ALL of your extra money on the lowest balance or the highest interest debt until it is gone and then you move onto the next one in the list. For what it's worth, I prefer the lowest balance method, you see progress faster."

negative: "The ""price"" is the price of the last transaction that actually took place. According to Motley Fool wiki: A stock price is determined by what was last paid for it. During market hours (usually weekdays from 9:30AM-4:00PM eastern), a heavily traded issue will see its price change several times per second. A stock's price is, for many purposes, considered unchanged outside of market hours. Roughly speaking, a transaction is executed when an offer to buy matches an offer to sell. These offers are listed in the Order Book for a stock (Example: GOOG at Yahoo Finance).  This is actively updated during trading hours. This lists all the currently active buy (""bid"") and sell (""ask"") orders for a stock, and looks like this:  You'll notice that the stock price (again, the last sale price) will (usually*) be between the highest bid and the lowest ask price. * Exception: When all the buy or sell prices have moved down or up, but no trades have executed yet."

negative: "Benninga's book(s) are pretty much the best crash course to financial modelling with Excel - be aware though, he has two distinct types of book. One is more of a walk-through of financial principles in Excel('Principles of Finance with Excel, 2nd Ed.'), and the other could better be described as a 'glossary' of financial applications in Excel(the oft-recommended 'Financial Modeling') . As far as I'm aware, both contain roughly the same volume of information about the same topics (could be some minor differences, as the walk-through-style book is newer), but are taught in somewhat different ways. It might be useful to obtain a copy of one or the other from a library and see if you enjoy the style of the book before purchasing it. I was fortunate enough to have a roommate where between us, we have both, but doing this individually is a 200+ dollar endeavor, and you will only be duplicating identical information. ;)  If you're interested in reading other interesting material, that may help you develop different perspectives/insight into investing, I would suggest, aside from reading the usual stuff (Intelligent Investor, Random Walk, etc), also obtaining a copy of Seth Klarman's ""Margin of Safety"". You'll have to do so in .pdf form, as the book is entirely out of print (and from what I've heard, Klarman himself bought out many retailers of all of their copies and had them destroyed), but it's an interesting read, that has a lot of modern relevance -  perhaps best evidenced by the fact that it's author, president of one of the largest hedge funds in the world, no longer wants it in print."

negative: "You might consider learning how the ""matching"" or ""pairing"" system in the market operates.  The actual exchange only happens when both a buyer and a seller overlap their respect quotes.   Sometimes orders ""go to market"" for a particular volume.  Eg get me 10,000 Microsoft shares now.  which means that the price starts at the current lowest seller, and works up the price list until the volume is met.  Like all market it trades, it has it's advantages, and it's dangers.  If you are confident Microsoft is going to bull, you want those shares now, confident you'll recoup the cost.  Where if you put in a priced order, you might get only none or some shares. Same as when you sell.  If you see the price (which is the price of the last completed ""successful"" trade.  and think ""I'm going to sell 1000 shares"". then you give the order to the market (or broker), and then the same as what happened as before.  the highest bidder gets as much as they asked for, if there's still shares left over, they go to the next bidder, and so on down the price... and the last completed ""successful"" trade is when your last sale is made at the lowest price of your batch. If you're selling, and selling 100,000 shares. And the highest bidder wants 1,000,000 shares you'll only see the price drop to that guys bid.  Why will it drop (off the quoted price?).  Because the quoted price is the LAST sale, clearly if there's someone still with an open bid on the market...then either he wants more shares than were available (the price stays same), or his bid wasn't as high as the last bid (so when you sale goes through, it will be at the price he's offering).   Which is why being able to see the price queues is important on large traders. It is also why it can be important put stops and limits on your trades, een through you can still get gapped if you're unlucky.  However putting prices (""Open Orders"" vs ""(at)Market Orders"") can mean that you're sitting there waiting for a bounce/spike while the action is all going on without you). safer but not as much gain (maybe ;) ) that's the excitement of the market, for every option there's advantages...and risks... (eg missing out) There are also issues with stock movement, shadowing, and stop hunting, which can influence the price. But the stuff in the long paragraphs is the technical reasons."

negative: The price of a share has two components: Bid: The highest price that someone who wants to buy shares is willing to pay for them. Ask: The lowest price that someone who has a share is willing to sell it for. The ask is always higher than the bid, since if they were equal the buyer and seller would have a deal, make a transaction, and that repeats until they are not equal. For stock with high volume, there is usually a very small difference between the bid and ask, but a stock with lower volume could have a major difference. When you say that the share price is $100, that could mean different things. You could be talking about the price that the shares sold for in the most recent transaction (and that might not even be between the current bid and ask), or you could be talking about any of the bid, the ask, or some value in between them. If you have shares that you are interested in selling, then the bid is what you could immediately sell a share for. If you sell a share for $100, that means someone was willing to pay you $100 for it. If after buying it, they still want to buy more for $100 each, or someone else does, then the bid is still $100, and you haven't changed the price. If no one else is willing to pay more than $90 for a share, then the price would drop to $90 next time a transaction takes place and thats what you would be able to immediately sell the next share for.

negative: "Realize this is almost a year old, but I just wanted to comment on something in Dynas' answer above...  ""Whenever you trade always think about what the other guys is thinking. Sometimes we forget their is someone else on the other side of my trade that thinks essentially the exact opposite of me. Its a zero sum game."" From a market maker's perspective, their primary goal is not necessarily to make money by you being wrong, it is to make money on the bid-offer spread and hedging their book (and potentially interalize). That being said, the market maker would likely be quoting one side of the market away from top of the book if they don't want to take exposure in that direction (i.e. their bid will be lower than the highest bid available or their offer higher than the lowest offer available). This isn't really going to change anything if you're trading on an exchange, but important to consider if you can only see the prices your broker/dealer provides to you and they are your counterparty in the trade."

negative: "- In a quote driven market, must every investor trade with a market        maker? In other words, two parties that are both not market makers        cannot trade between themselves directly? In a way yes, all trades go through a market maker but those trades can be orders put in place by a ""person"" IE: you, or me. - Does a quote driven market only display the ""best"" bid and ask        prices proposed by the market makers? In other words, only the        highest bid price among all the market makers is displayed, and        other lower bid prices by other market makers are not? Similarly,        only the lowest ask price over all market makers is displayed, and        other higher ask prices by other market makers are not? No, you can see other lower bid and higher ask prices. - In a order-driven market, is it meaningful to talk about ""the current stock price"", which is the price of last transaction? Well that's kind of an opinion. Information is information so it won't be bad to know it. Personally I would say the bid and ask price is more important. However in the real world these prices are changing constantly and quickly so realistically it is easier to keep track of the quote price and most likely the bid/ask spread is small and the quote will fall in between. The less liquid a security is the more important the bid/ask is. -- This goes for all market types. - For a specific asset, will there be several transactions happened at    the same time but with different prices? Today with electronic markets, trades can happen so quickly it's difficult to say. In the US stock market trades happen one at a time but there is no set time limit between each trade. So within 1 second you can have a trade be $50 or $50.04. However it will only go to $50.04 when the lower ask prices have been exhausted.   - Does an order driven market have market makers?  By definition, no. - What are some examples of quote driven and order driven financial markets, in which investors are commonly trading stocks and derivatives, especially in U.S.? Quote driven market: Bond market, Forex. Order driven market: NYSE comes from an order driven market but now would be better classified as a ""hybird market"" Conclusion: If you are asking in order to better understand today's stock markets then these old definitions of Quote market or Order market may not work. The big markets in the real world are neither. (IE: Nasdaq, NYSE...) The NYSE and Nasdaq are better classified as a ""hybird market"" as they use more then a single tactic from both market types to insure market liquidity, and transparency. Markets these days are strongly electronic, fast, and fairly liquid in most cases. Here are some resources to better understand these markets: An Introduction To Securities Markets The NYSE And Nasdaq: How They Work Understanding Order Execution"

negative: You don't see Buying and Selling. You see Bid and Ask. Best Bid--Highest Price someone is willing to pay to buy a stock. Best Ask - Lowest price someone is willing to accept to sell a stock. As for your second question, if you can look up Accumulation/Distribution Algorithm and Iceberg Order, you will get basic idea.

negative: "Most of the time* you're selling to other investors, not back to the company. The stock market is a collection of bid (buy offers) and asks (sell offers). When you sell your stock as a retail investor at the ""market"" price you're essentially just meeting whatever standing bid offers are on the market.  For very liquid stocks (e.g. Apple), you can pretty much always get the displayed price because so many stocks are being traded. However during periods of very high volatility or for low-volume stocks, the quoted price may not be indicative of what you actually pay.  As an example, let's say you have 5 stocks you're trying to sell and the bid-side order book is 2 stocks for $105, 2 for $100, and 5 for $95. In this scenario the quoted price will be $105 (the best bid price), but if you accept market price you'll settle 2 for 105, 2 for 100, and 1 for 95. After your sell order goes through, the new quoted price will be $95. For high volume stocks, there will usually be so many orders near the midpoint price ($105, in this case) that you won't see any price slippage for small orders.  You can also post limit orders, which are essentially open orders waiting to be filled like in the above example. They ensure you get the price you want, but you have no way to guarantee they'll be filled or not.  Edit: as a cool example, check out the bitcoin GDAX on coinbase for a live example of what the order book looks like for stocks. You'll see that the price of bitcoin will drift towards whichever direction has the less dense order book (e.g. price drifts upwards when there are far more bids than asks.)"

negative: "There are two distinct questions that may be of interest to you. Both questions are relevant for funds that need to buy or sell large orders that you are talking about. The answer depends on your order type and the current market state such as the level 2 order book. Suppose there are no iceberg or hidden orders and the order book (image courtesy of this question) currently is:  An unlimited (""at market"") buy order for 12,000 shares gets filled immediately: it gets 1,100 shares at 180.03 (1,100@180.03), 9,700 at 180.04 and 1,200 at 180.05. After this order, the lowest ask price becomes 180.05 and the highest bid is obviously still 180.02 (because the previous order was a 'market order'). A limited buy order for 12,000 shares with a price limit of 180.04 gets the first two fills just like the market order: 1,100 shares at 180.03 and 9,700 at 180.04. However, the remainder of the order will establish a new bid price level for 1,200 shares at 180.04. It is possible to enter an unlimited buy order that exhausts the book. However, such a trade would often be considered a mis-trade and either (i) be cancelled by the broker, (ii) be cancelled or undone by the exchange, or (iii) hit the maximum price move a stock is allowed per day (""limit up""). Funds and banks often have to buy or sell large quantities, just like you have described. However they usually do not punch through order book levels as I described before. Instead they would spread out the order over time and buy a smaller quantity several times throughout the day. Simple algorithms attempt to get a price close to the time-weighted average price (TWAP) or volume-weighted average price (VWAP) and would buy a smaller amount every N minutes. Despite splitting the order into smaller pieces the price usually moves against the trader for many reasons. There are many models to estimate the market impact of an order before executing it and many brokers have their own model, for example Deutsche Bank. There is considerable research on ""market impact"" if you are interested. I understand the general principal that when significant buy orders   comes in relative to the sell orders price goes up and when a   significant sell order comes in relative to buy orders it goes down. I consider this statement wrong or at least misleading. First, stocks can jump in price without or with very little volume. Consider a company that releases a negative earnings surprise over night. On the next day the stock may open 20% lower without any orders having matched for any price in between. The price moved because the perception of the stocks value changed, not because of buy or sell pressure. Second, buy and sell pressure have an effect on the price because of the underlying reason, and not necessarily/only because of the mechanics of the market. Assume you were prepared to sell HyperNanoTech stock, but suddenly there's a lot of buzz and your colleagues are talking about buying it. Would you still sell it for the same price? I wouldn't. I would try to find out how much they are prepared to buy it for. In other words, buy pressure can be the consequence of successful marketing of the stock and the marketing buzz is what changes the price."

negative: The options market requires much more attention to avoid the situation you're describing. An overnight $10 ask will remain on the books most likely as Good-Til-Canceled.  The first to bid the low order gets it.  If traders are paying attention, which they probably are then they will bid at $10.  If not, they will bid immediately at $20. If they crossed the order, it would be filled at their higher than $10 bid. This is all governed by the exchange where the ask is posted, and most implement price-time priority.

negative: If the stock has low liquidity, yes there could be times when there are no buyers or sellers at a specific price, so if you put a limit order to buy or sell at a price with no other corresponding sellers or buyers, then your order may take a while to get executed or it may not be executed at all. You can usually tell if a stock has low liquidity by the small size of the average daily volume, the lack of order depth and the large size of the gap between bids and offers. So if a stock for example has last sale price of $0.50, has a highest bid price of $0.40 and a lowest offer price of $0.60, and an average daily volume of 10000 share, it is likely to be very illiquid. So if you try to buy or sell at around the $0.50 mark it might take you a long time to buy or sell this stock at this price.

negative: "While the question is highly subjective as you noted, putting extra money will of course save you interest payments, it depends on how much ""enjoyment"" is worth now. I would suggest you to not be overly aggressive as you might dig yourself a ditch, your minimum monthly payments might get adjust upwards if some of these loans are student loans as it might seem you have a higher degree of disposable income to play with. Be aggressive in paying them off but not to aggressive, I also think the interest is tax deductible. What it really comes down to is, how much more interest do you want to pay them for enjoyment now, 50 months is not long its just north of 4 years. I'd say if you think you can put 800 extra towards them, don't. Instead if it were me I would put an extra 400 towards the highest until its paid and then take the 400 plus the monthly minimum and add that to the next highest and keep the other 400 for a rainy day, you will still get paid off quick but will leave yourself some scratch if necessary."

negative: "The current stock price you're referring to is actually the price of the last trade.  It is a historical price – but during market hours, that's usually mere seconds ago for very liquid stocks. Whereas, the bid and ask are the best potential prices that buyers and sellers are willing to transact at: the bid for the buying side, and the ask for the selling side.  But, think of the bid and ask prices you see as ""tip of the iceberg"" prices.  That is: The ""Bid: 13.20 x200"" is an indication that there are potential buyers bidding $13.20 for up to 200 shares.  Their bids are the highest currently bid; and there are others in line behind with lower bid prices.  So the ""bid"" you're seeing is actually the best bid price at that moment.  If you entered a ""market"" order to sell more than 200 shares, part of your order would likely be filled at a lower price. The ""Ask: 13.27 x1,000"" is an indication that there are potential sellers asking $13.27 for up to 1000 shares.  Their ask prices are the lowest currently asked; and there are others in line behind with higher ask prices.  So the ""ask"" you're seeing is the best asking price at that moment.  If you entered a ""market"" order to buy more than 1000 shares, part of your order would likely be filled at a higher price. A transaction takes place when either a potential buyer is willing to pay the asking price, or a potential seller is willing to accept the bid price, or else they meet in the middle if both buyers and sellers change their orders. Note: There are primarily two kinds of stock exchanges.  The one I just described is a typical order-driven matched bargain market, and perhaps the kind you're referring to. The other kind is a quote-driven over-the-counter market where there is a market-maker, as JohnFx already mentioned.  In those cases, the spread between the bid & ask goes to the market maker as compensation for making a market in a stock.  For a liquid stock that is easy for the market maker to turn around and buy/sell to somebody else, the spread is small (narrow).  For illiquid stocks that are harder to deal in, the spread is larger (wide) to compensate the market-maker having to potentially carry the stock in inventory for some period of time, during which there's a risk to him if it moves in the wrong direction.    Finally ... if you wanted to buy 1000 shares, you could enter a market order, in which case as described above you'll pay $13.27.  If you wanted to buy your shares at no more than $13.22 instead, i.e. the so-called ""current"" price, then you would enter a limit order for 1000 shares at $13.22.  And more to the point, your order would become the new highest-bid price (until somebody else accepts your bid for their shares.)  Of course, there's no guarantee that with a limit order that you will get filled; your order could expire at the end of the day if nobody accepts your bid."

negative: "This is a complicated subject, because professional traders don't rely on brokers for stock quotes.  They have access to market data using Level II terminals, which show them all of the prices (buy and sell) for a given stock.   Every publicly traded stock (at least in the U.S.) relies on firms called ""market makers"".  Market makers are the ones who ultimately actually buy and sell the shares of companies, making their money on the difference between what they bought the stock at and what they can sell it for.  Sometimes those margins can be in hundreds of a cent per share, but if you trade enough shares...well, it adds up. The most widely traded stocks (Apple, Microsoft, BP, etc) may have hundreds of market makers who are willing to handle share trades.  Each market maker sets their own price on what they'll pay (the ""bid"") to buy someone's stock who wants to sell and what they'll sell (the ""ask"") that share for to someone who wants to buy it.   When a market maker wants to be competitive, he may price his bid/ask pretty aggressively, because automated trading systems are designed to seek out the best bid/ask prices for their trade executions.  As such, you might get a huge chunk of market makers in a popular stock to all set their prices almost identically to one another.  Other market makers who aren't as enthusiastic will set less competitive prices, so they don't get much (maybe no) business.  In any case, what you see when you pull up a stock quote is called the ""best bid/ask"" price.  In other words, you're seeing the highest price a market maker will pay to buy that stock, and the lowest price that a market maker will sell that stock.  You may get a best bid from one market maker and a best ask from a different one.  In any case, consumers must be given best bid/ask prices. Market makers actually control the prices of shares.  They can see what's out there in terms of what people want to buy or sell, and they modify their prices accordingly.  If they see a bunch of sell orders coming into the system, they'll start dropping prices, and if people are in a buying mood then they'll raise prices. Market makers can actually ignore requests for trades (whether buy or sell) if they choose to, and sometimes they do, which is why a limit order (a request to buy/sell a stock at a specific price, regardless of its current actual price) that someone places may go unfilled and die at the end of the trading session.  No market maker is willing to fill the order. Nowadays, these systems are largely automated, so they operate according to complex rules defined by their owners.  Very few trades actually involve human intervention, because people can't digest the information at a fast enough pace to keep up with automated platforms. So that's the basics of how share prices work.  I hope this answered your question without being too confusing! Good luck!"

negative: Strictly from a fastest payback standpoint, the rule is to make all minimum payments and send any extra funds to the highest interest loan next.  This will result in the lowest interest paid each year.  The decision to consolidate depends on the impact it will have to both your payment and overall payoff schedule. It sounds like your priority might need to be cash flow and not overall savings. e.g. taking a 4% loan that has a high payment, but stretching it over more time can lower the payment, even at a bit higher rate. You just need to be aware of the cost and decide based on what you can live with. I hope you are in a good field that would see improvements to your income over these next few years.

negative: It is unlikely that buying 100 shares will have any effect on a stock's price, unless the stock's average trading volume is incredibly low.  That being said, no matter how many share you buy, there's no way to know what the impact on the price will be, because that's only one factor in how shares are priced.  If anyone could figure out the answer to your question then they'd be extremely rich, because they'd simply watch for big share trades and then buy those stocks on the way up. The market makers who actually execute the trades are the ones who set the prices, and most stocks have multiple market makers trading the stock, so the bid/ask you see is the highest bid and lowest ask.  The market makers set the price based on what the trend of the stock is.  If, for instance, there's a large number of sell orders against a stock, the market makers will start dropping the bid prices as they fill execution orders, and as they see buy orders increase, they'll raise ask prices as they fill execution orders.  The market makers earn the difference between what they paid to buy someone's stock who was selling and what they get from someone else who buys it. This is a simplified explanation, so pro traders, don't beat me up! (grin) So, basically, it takes quite a bit of share volume in one direction or another to affect a stock's price.  I can guarantee a 100-share trade wouldn't even be noticed by market makers. I hope this helps. Good luck!

negative: At Belisted.org we offer the chance to have your business listed in top directories. You can choose a custom number of the best directories from our extensive list. Every order comes with a detailed report of the places that we have submitted your business to as well as all the log-in information. We offer the cheapest local business lisitings submission services and the highest quality on the planet. You will enjoy our Easy Ordering method no matter what size the order, be it bulk or otherwise.

negative: Bookstores don't need their own warehouses to do that. They just order it from the big suppliers. I can order any book I want to be delivered to the next bookstore, and it will be there the next day at the latest, sometimes even within hours.

negative: > we make a trade-off between time to execute and market impact.  Is your time frame any longer than intraday? I imagine you wouldn't want to carry that risk overnight if you're a broker or selling a route..  > we will join the bid for some fraction of our size, and also hit the offer when it looks like the price might be moving away from us  So, say for instance you join a bid a few levels down, you aren't really get filled, you start hitting the offer and eventually you realize you're competing with someone for the shares offered, so you take out the price level and bid on all the exchanges so that you're first on the bid at that level, then repeat until someone that can match your appetite starts to fill you on the bid?  > In some certain situations we will even sweep the book several levels deep to avoid tipping off market makers and having them adjust in anticipation of the rest of our order.  Right, so say you need 100k shares, there are 10k offered at 9.98, 25k offered at 9.99, and 65k at 10.00, you might just enter an intermarket sweep order of 100k @ 10 limit and hope that you can get most of the shares off before everyone can cancel?  I imagine there has to be a lot of bidding it up to attract sellers and then letting people take out your bids all day...  I have a few other questions I would appreciate your insight on. Just trying to ascertain how orders are filled when, as you put it, time is more important than market impact to the client - when they need to take a large amount of liquidity as quickly as possible and as orderly as possible.  Let me know if you'd rather I pm you about this or the additional questions, I work in the industry as well so I know privacy is paramount.

negative: "I may be underestimating your knowledge of how exchanges work; if so, I apologize.  If not, then I believe the answer is relatively straightforward. Lets say price of a stock at time t1 is 15$ .  There are many types of price that an exchange reports to the public (as discussed below); let's say that you're referring to the most recent trade price.  That is, the last time a trade executed between a willing buyer and a willing seller was at $15.00. Lets say a significant buy order of 1M shares came in to the market. Here I believe might be a misunderstanding on your part.  I think you're assuming that the buy order must necessarily be requesting a price of $15.00 because that was the last published price at time t1.  In fact, orders can request any price they want.  It's totally okay for someone to request to buy at $10.00.  Presumably nobody will want to sell to him, but it's still a perfectly valid buy order. But let's continue under the assumptions that at t1: This makes the bid $14.99 and the ask $15.00.  (NYSE also publishes these prices.) There aren't enough people selling that stock. It's quite rare (in major US equities) for anyone to place a buy order that exceeds the total available shares listed for sale at all prices.  What I think you mean is that 1M is larger than the amount of currently-listed sell requests at the ask of $15.00. So say of the 1M only 100,000 had a matching sell order and others are waiting. So this means that there were exactly 100,000 shares waiting to be sold at the ask of $15.00, and that all other sellers currently in the market told NYSE they were only willing to sell for a price of $15.01 or higher.  If there had been more shares available at $15.00, then NYSE would have matched them. This would be a trigger to the automated system to start increasing the price. Here is another point of misunderstanding, I think.  NYSE's automated system does not invent a new, higher price to publish at this point.  Instead it simply reports the last trade price (still $15.00), and now that all of the willing sellers at $15.00 have been matched, NYSE also publishes the new ask price of $15.01.  It's not that NYSE has decided $15.01 is the new price for the stock; it's that $15.01 is now the lowest price at which anyone (known to NYSE) is willing to sell.  If nobody happened to be interested in selling at $15.01 at t1, but there were people interested in selling at $15.02, then the new published ask would be $15.02 instead of $15.01 -- not because NYSE decided it, but just because those happened to be the facts at the time. Similarly, the new bid is most likely now $15.00, assuming the person who placed the order for 1M shares did not cancel the remaining unmatched 900,000 shares of his/her order.  That is, $15.00 is now the highest price at which anyone (known to NYSE) is willing to buy. How much time does the automated system wait to increment the price, the frequency of the price change and by what percentage to increment etc. So I think the answer to all these questions is that the automated system does none of these things.  It merely publishes information about (a) the last trade price, (b) the price that is currently the lowest price at which anyone has expressed a willingness to sell, and (c) the price that is currently the highest price at which anyone has expressed a willingness to buy. ::edit:: Oh, I forgot to answer your primary question. Can we estimate the impact of a large buy order on the share price? Not only can we estimate the impact, but we can know it explicitly.  Because the exchange publishes information on all the orders it knows about, anyone tracking that information can deduce that (in this example) there were exactly 100,000 shares waiting to be purchased at $15.00.  So if a ""large buy order"" of 1M shares comes in at $15.00, then we know that all of the people waiting to sell at $15.00 will be matched, and the new lowest ask price will be $15.01 (or whatever was the next lowest sell price that the exchange had previously published)."

negative: I can't say I know everything about the underlying details, but from what I understand, your limit buy adds to the bid side of open orders, and one possibility is that someone placed a market order to sell when the bid price for the stock fell to $10 which was matched to your open limit order. So using your terminology, I would say the spot bid price is what fell to $10, even if for a brief moment. Whether or not it is possible for your order to be filled when the limit buy price is deeper than the current bid price is beyond me. It may have something to do with lot sizes.

negative: Is there anything here I should be deathly concerned about? A concern I see is the variable rate loans. Do you understand the maximum rate they can get to? At this time those rates are low, but if you are going to put funds against the highest rate loan, make sure the order doesn't change without you noticing it. What is a good mode of attack here?  The best mode of attack is to pay off the one with the highest rate first by paying more than the minimum. When that is done roll over the money you were paying for that loan to the next highest. Note if a loan balance get to be very low, you can put extra funds against this low balance loan to be done with it. Investigate loan forgiveness programs. The federal government has loan forgiveness programs for certain job positions, if you work for them for a number of years. Some employers also have these programs.  What are the payoff dates for the other loans? My inexact calculations put a bunch in about 2020 but some as late as 2030. You may need to talk to your lender. They might have a calculator on their website.  Why do my Citi loans have a higher balance than the original payoff amounts? Some loans are subsidized by the federal government. This covers the interest while the student is still in school. Non-subsidized federal loans and private loans don't have this feature, so their balance can grow while the student is in school.

negative: In general a stock can open at absolutely any price with no regard for the closing price or after hours price the previous day. The opening price will be determined by the best bid and offer made by people who decide to trade the next day.  Some of the those people may have put orders in on a prior day that are still on the books and matter, but there's a lot of time overnight for people to cancel orders and enter new ones, which is especially likely to happen if there was substantive news overnight. As for what you can do in your case, you have the same options that you always had:  Sell or hold.  If you're selling, you can sell after hours, in the pre-open hours, or during the trading day.  There's nothing we can say about this case that's really any different than we can say about any other stock on any other day.

negative: buy above the current price in the stock market You can do that, but what is the purpose to do so ? Brokers take the limit price of your order as the highest price you are going to pay. So if an order can be fulfilled below the limit they will do so.  can I sell below the current price  You can put in a order to do so. But what I have seen with my current broker is that the order never reached the market and wasn't executed at all. The broker might have some safeguards or process in place to stop me from doing so. Not sure how other brokers deal with it.

negative: The Limit Order are matched based on amount and time. The orders are listed Highest to Lowest on the Buy Side. The orders are listed Lowest to Highest on the Sell Side. If there are 2 Sell orders for same amount the order which is first in time [fractions of milliseconds] is first.  The about is the example as to how the orders would look like on any exchange.  Now the highest price the buyer is ready to pay is 20.21 and the lowest price a seller is ready to sell for is 20.25. Hence there is no trade. Now if a new Buy order comes in at 20.25, it matches with the sell and the deal is made. If a new Buy order comes in at 20.30, it still matches at 20.25. Similarly if a Sell order come in at 20.21, it matches and a deal is made. If a Sell order come in at 20.11, it still matches 20.21.   Incase of market order, with the above example if there is a Buy order, it would match with the lowest sell order at 20.25, if there is not enough quantity , it would match the remaining quantity to the next highest at 20.31 and continue down. Similarly if there is a Sell market order, the it would match to the maximum a seller is ready to buy, ie 20.21, if there is not sufficient buy quantity at 20.21, it will match with next for 20.19   If say there are new buy order at 20.22 and sell orders at 20.24, these will sit first the the above queue to be matched. In your above example the Lowest Sell order was at 20.10 at time t1 and hence any buy order after time t1 for amount 20.10 or greater would match to this and the price would be 20.10. However if the Buy order was first ie at t1 there was a buy order for 20.21 and then at time later than t1, there is a sell order for say 20.10 [amount less than or equal to 20.21] it would match for 20.21. Essentially the market looks at who was the first to sell at lower price or who was the first to buy at higher price and then decide the trade.  Edit [To Clarify xyz]: Say if there is an Sell order at $10 Qty 100. There is a buyer who is willing to pay Max $20 and is looking for Qty 500. Your key assumption that the Buyer does not know the current SELL price of $10 is incorrect. Now there are multiple things, the Buyer knows the lowest Sell order is at $10, he can put a matching Buy order at $10 Qty 100, and say $11 Qty 100 etc. This is painful. Second, lets say he puts a Buy order at $10 Qty 100, by the time the order hits the system someone else has put the trade at $10 and his order is fulfilled. So this buyer has to keep looking at booking and keep making adjustments, if its a large order, it would be extremely difficult and frustrating for this Buyer. Hence the logic of giving preference. The later Buy order says ... The Max I can pay is $20, match eveything at the current price and get the required shares.

negative: A bid is an offer to buy something on an order book, so for example you may post an offer to buy one share, at $5. An ask is an offer to sell something on an order book, at a set price. For example you may post an offer to sell shares at $6. A trade happens when there are bids/asks that overlap each other, or are at the same price, so there is always a spread of at least one of the smallest currency unit the exchange allows. Betting that the price of an asset will go down, traditionally by borrowing some of that asset and then selling it, hoping to buy it back at a lower price and pocket the difference (minus interest). So, let's say as per your example you borrow 100 shares of company 'X', expecting the price of them to go down. You take your shares to the market and sell them - you make a market sell order (a market 'ask'). This matches against a bid and you receive a price of $5 per share. Now, let's pretend that you change your mind and you think the price is going to go up, you instantly regret your decision. In order to pay back the shares, you now need to buy back your shares as $6 - which is the price off the ask offers on the order book. Because of this spread, you have lost money. You sold at a low price and bought at a high price, meaning it costs you more money to repay your borrowed shares. So, when you are shorting you need the spread to be as tight as possible.

negative: "I don't have enough reputation in this community to comment yet, so this ""answer"" is really just a minor furtherance of JoeTaxpayer's comment... THe only thing I might add to this great answer - make all minimum payments, and send all extra available cash to the highest interest card. If OP will pay in full after 6 month, this may make little difference, but it will be a few dollars in his pocket instead of the bank. – JoeTaxpayer♦ Dec 2 at 17:42 ...on Ben Miller's excellent answer. Once you have taken JoeTaxpayer's advice and ordered your cards by interest rate and have paid off the highest interest card first, take that same payment and add it to your next-highest card's minimum payment. Once THAT is payed off, take the combined amounts that you were paying to cards one and two and apply it all to card three along with its minimum payment. You see where this is going. By aggregating your payments thusly, each card will get paid off successively more quickly than the previous one, without increasing your overall payments to the cards, and you are retiring the highest-interest debt first. Your last card will then be paid off in record time, because you have combined all of the payments for cards 1-4. One other amplification: Since we don't know which account has which interest rate, it may be more advantageous to order them by balance, with the smallest first. That way you retire the first card quickly, which gives you a sense of accomplishment, and by the time you reach your highest balance card, you have snowballed all of your payments and are now throwing boulders instead of pebbles at it. You'll have to do that math to see which method has the most benefit. Then roll it all into the car payment. Then roll it into your student debt. Etc."

negative: Many of the Bitcoin exchanges mimic stock exchanges, though they're much more rudimentary offering only simple buy/sell/cancel orders.  It's fairly normal for retail stock brokerage accounts to allow other sorts of more complex orders, where once a certain criteria is met, (the price falls below some $ threshold, or has a movement greater than some %) then your order is executed.  The space between the current buy order and the current sell order is the bid/ask spread, it's not really about timing.  Person X will buy at $100, person Y will sell at $102.  If both had a price set at $101, they would just transact.  Both parties think they can do a little bit better than the current offer.  The width of the bid/ask spread is not universal by any means.  The current highest buy order and the current lowest sell order, are both the current price.  The current quoted market price is generally the price of the last transaction, whether it's buy or sell.

negative: "What if everyone decided to sell all the shares at a given moment, let's say when the stock is trading at $40? It would fall to the lowest bid price, which could be $0.01 if someone had that bid in place. Here is an example which I happened to find online:  Notice there are orders to buy at half the market price and lower... probably all the way down to pennies.  If there were enough selling activity to fill all of those bids you see, then the market price would be the lowest bid on the screen.  Alternatively, the bid orders could be pulled (cancelled), which would also let the price free-fall to the lowest bid even if there were few actual sellers. Bid-stuffing is what HFT (high frequency trading) algorithms sometimes do, which some say caused the Flash Crash of May 2010.  The computers ""stuff"" bids into the order book, making it look like there is demand in order to trigger a market reaction, then they pull the bids to make the market fall.  This sort of thing happens all the time and Nanex documents it http://www.nanex.net/FlashCrash/OngoingResearch.html Quote stuffing defined: http://www.investopedia.com/terms/q/quote-stuffing.asp I remember the day of the Flash Crash very well.  I found this video on youtube of CNBC at that time.  Watch from the 5:00 min mark on the video as Jim Crammer talks about PG easily not being worth the price of the market at that time.  He said ""Who cares?"", ""Its not a real price"", ""$49.25 bid for 50,000 shares if I were at my hedge fund.""  http://www.youtube.com/watch?v=86g4_w4j3jU You can value a stock how you want, but its only actually worth what someone will give you for it. More examples: Anadarko Petroleum, which as we noted in today's EOD post, lost $45 billion in market cap in 45 milliseconds (a collapse rate of $1 billion per millisecond), flash crashing from $90 all the way to an (allegedly illegal) stub quote of $0.01. http://www.zerohedge.com/news/2013-05-17/how-last-second-flash-crash-pushed-sp-500-1667-1666 How 10,000 Contracts Crashed The Market: A Visual Deconstruction Of Last Night's E-Mini Flash Crash http://www.zerohedge.com/news/2012-12-21/how-10000-contracts-crashed-market-visual-deconstruction-last-nights-e-mini-flash-cr Symantec Flash-Crash Destroys Over $1.5 Billion In Less Than A Second http://www.zerohedge.com/news/2013-04-30/symantec-flash-crash-destroys-over-15-billion-less-second This sort of thing happens so often, I don't pay much attention anymore."