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As computers don't have fingers to count on they must use another method. Their method is to use the presence or absence of electricity as the numbers 1 and 0.

Each binary digit is called a bit.

Eight bits are a byte.

Think of binary like a light switch. If the switch is off the light is off. That is a 0. If the switch is on the light is on. That is a 1.

A binary number then looks different from what we are used to. Where we would write 13 a computer would represent this as ON ON OFF ON, or 1101.

Why is this? What does each column represent?

Next: Using Exponents