Ceramic capacitors: how to read 2-digit markings?
The brown capacitors have values in picoFarads

eg
 47 = 47 picoFarad = 47 pF = 0.000 000 000 047 Farad !
 10 = 10 pF 



For the yellow and green capacitors with markings of the form

anb



Here n = nanoFarad = nF.


  1n0 = 1.0 nF
  2n2 = 2.2 nF
  6n8 = 6.8 nF


Note that the use of xNx here is (probably) unqiue to capacitors in the nF range - I do not recall seeing eg xPx or xUx markings ever.

However page 70 of this superbVishay ceramic single layer capacitors document suggests you might expect to meet any of eg
p68 = 0.68 pF
n15 = 0.15nF = 150 pF
5p0 = 5 pF etc

The green dot is quite likely to be a voltage rating, but alas I don't know what system it uses. There are several different colour/voltage systems. Typically this sort of capacitor is 50 Volt rated but this is not certain.



More usual nnX 3 digit markings

Most capacitor numerical markings are 3 digit and express the value in pF (pico Farad = 10^-12 Farad) with the last digit being a power of 10 multiplier.

So


  223 = 22,000 pF = 22 nF = 0.022 uF = 0.000 000 022 F
  106 = 10 000 000 pF = 10 uF
  100 = 10 pF and NOT 100 pF etc




Part of a larger tutorial series on capacitors. Deals in colour codes. Does not answer exact question but is useful

This does NOT answer the original question but is useful