Binary number

A binary number is a way of counting. It uses only two digits, 0 and 1. To count in binary, you add 1 every time the number gets past 1. For example, the binary number for the number three is 11 because it is two 1's (1+1 = 2 and 2+1 = 3). Binary numbers are used a lot in computers because computers use 0s and 1s to represent data. That way computers can record and process information quickly.