# bit

##### Information unit
Name Symbol Quantity Expressed in terms of SI base units
bit bit data ### Definition

The bit, symbol bit, is the unit of digital information.

One bit represents a single binary digit which can be either 0 or 1.

The bit is the smallest unit of information and storage.

### Number bases

In the decimal number system, numbers are represented as groups of digits. Each digit can represent any value from 0 to 9. Numbers greater than 9 are represented by additional digits to the left, forming an array of digits. Each additional digit increases the number of different values that can be represented by a factor of 10.

In binary, numbers are also represented as groups of digits. However, the value that each digit can represent is restricted to either 0 or 1. Numbers greater than 1 are represented by additional digits to the left, forming an array of digits in a similar manner to the decimal system. In binary, each additional digit increases the number of different values that can be represented by a factor of 2.

### The nibble

A nibble is a group of 4 bits. The nibble is used in the context of hexadecimal numbers, since a nibble has the same amount of information as one hexadecimal digit. A group of 4 bits can be used to represent 24, or 16, different values.

 binary (base 2) hexadecimal (base 16) decimal (base 10) 0000 0 0 0001 1 1 0010 2 2 0011 3 3 0100 4 4 0101 5 5 0110 6 6 0111 7 7 1000 8 8 1001 9 9 1010 A 10 1011 B 11 1100 C 12 1101 D 13 1110 E 14 1111 F 15

### The byte

The byte, symbol B, is a unit of digital information consisting of a group of 8 bits. A group of 8 bits can represent 28, or 256, different values.