Binary Numbers

Computers don't think in the numbers we use (0-9). They think in **binary**, which only uses two digits: 0 and 1. Everything a computer does, from showing a picture to running a game, is broken down into a series of 0s and 1s.

Our number system is "base-10" because we have 10 digits. Binary is "base-2".

Let's see how it works. In base-10, each place value is a power of 10:
... 1000s, 100s, 10s, 1s

In binary, each place value is a power of 2:
... 16s, 8s, 4s, 2s, 1s

So, the number 5 in binary is 101. Why?
- 1 in the 4s place = 4
- 0 in the 2s place = 0
- 1 in the 1s place = 1
- 4 + 0 + 1 = 5

The number 10 in binary is 1010.
- 1 * 8 + 0 * 4 + 1 * 2 + 0 * 1 = 10.

Understanding binary is key to understanding how computers work at their most fundamental level.