In order to really understand IP addressing you should understand the powers of two.  While it may appear confusing initially, you simply start with the number two and keep doubling the previous number.  And that’s all there is to it.

1×2= 2

2×2 or 2×2 = 4

3×2 or 2x2x2 = 8

4×2 or 2x2x2x2 = 16

The important thing isn’t the multiplication; it is what is happening to the answers.  Each time the number doubles.  If we want to work out the powers we would write it like this.