# binary number system

- A method of representing numbers that has 2 as its base and uses only the digits 0 and 1. Each successive digit represents a power of 2. For example, 10011 represents (1 X 24) + (0 X 23) + (0 X 22) + (1 X 21) + (1 X 20), or 16 + 0 + 0 + 2 + 1, or 19.

The American Heritage® Science Dictionary
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