**bit**

##### Information unit

Name | Symbol | Quantity | Expressed in terms of SI base units | |

bit | bit | data | ||

## DefinitionThe bit, symbol bit, is the unit of digital information. |

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 2^{4}, 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 2^{8}, or 256, different values.