Is my inductor really 22µH?
There are two ways of marking parts...

A Three digit code for values from 10 and up

X Y Z
X - First digit
Y - Second digit
Z - Power of ten

220 would be 22 = 22 x 10^0 (1)
221 would be 220 = 22 x 10^1 (10)
222 would be 2,200 = 22 x 10^2 (100)
223 would be 22,000 = 22 x 10^3 (1000)


The Minimum for this coding would be 
100 = 10 x 10^0
and the Maximum would be
999 = 99,000,000,000 = 99 x 10^9 (1,000,000,000)

For values under 10

you use a character to replace the decimal point

e.g. 
3R3 = 3.3
R33 = 0.33

R is used for Ohms.

For resistors the value is usually in Ohms
For Capacitors the value is usually in pico farads

e.g. a Capacitor marked 103 would be 103 pF = 10 x 10^3 (1000) pF = 10nF = 0.01uF

For Inductors the value is usually in micro henrys
e.g. a Inductor marked 220 woulf be 22uH = 22 x 10^0 (1) uH

The part marked 3R3 is a 3.3 ohm resistor as R is used on resistors.