Smaller capacitors such as Ceramic capacitors often don’t have space to have the full spec written on them so they use a coding scheme to tell what they are.
This coding is usually in 2 or 3 digits, sometimes followed by a letter that defines tolerance.
For two digits
You simply read them as pico-Farads (pf). So 10 would mean 10 pF.
For three digits
You read the first two and then add the amount of zeros at back of the number as last digit says. So for example 101 would be 100 pF. And 100 would be 10 pf. (Yes sometimes same one can be represented either in 2 letter system or 3 letter system). 102 would be 1000 pF.
Other formats
You might also encounter capacitors that are coded like 2n0, which means they neither are in the 2 digit system nor the 3 digit system. 2n0 would mean 2.0 nF, where the n says the unit, which in this case was nano-Farad.
Tolerance
Sometimes the 2 and 3 digit capacitors also have a letter at back which represents the tolerance.
The tolerance is coded as follows: