Binary number
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A binary number is a number expressed in the base-2 numeral system or binary numeral system, a method for representing numbers that uses only two symbols for the natural numbers: typically "0" (zero) and "1" (one). A binary number may also refer to a rational number that has a finite representation in the binary numeral system, that is, the quotient of an integer by a power of two.
The base-2 numeral system is a positional notation with a radix of 2. Each digit is referred to as a bit, or binary digit. Because of its straightforward implementation in digital electronic circuitry using logic gates, the binary system is used by almost all modern computers and computer-based devices, as a preferred system of use, over various other human techniques of communication, because of the simplicity of the language and the noise immunity in physical implementation.
| Decimal number | Binary number | 
|---|---|
| 0 | 0 | 
| 1 | 1 | 
| 2 | 10 | 
| 3 | 11 | 
| 4 | 100 | 
| 5 | 101 | 
| 6 | 110 | 
| 7 | 111 | 
| 8 | 1000 | 
| 9 | 1001 | 
| 10 | 1010 | 
| 11 | 1011 | 
| 12 | 1100 | 
| 13 | 1101 | 
| 14 | 1110 | 
| 15 | 1111 |