binary numbers

Binary numbers are a way of counting using only two numbers: 0 and 1. We often use the numbers 0 to 9 to count, but computers use 0 and 1. That's why they are called binary numbers. Computers use binary numbers because they are easy to understand when they are turned into 0s and 1s. Each 0 or 1 can represent something in the computer like a letter or a picture. So if you have a bunch of 0s and 1s, the computer can "read" it. Binary numbers are the language computers use to understand what we tell them.