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# UnitInformationStorage

A unit of measure for quantities of information.

```
class UnitInformationStorage
```

## Overview

Use instances of [`UnitInformationStorage`](/documentation/Foundation/UnitInformationStorage) to represent quantities of information using the [`NSMeasurement`](/documentation/Foundation/NSMeasurement) class. The base unit of measure for information is the bit, with a nibble representing four bits and a byte representing eight bits.

Larger units of information expand on bits and bytes by orders of magnitude in both decimal and binary forms.

### Information Transfer

Units of bits commonly represent the amount of transferred information.

|Decimal Bits                                                                            |Coefficient|Binary Bits                                                                            |Coefficient|
|----------------------------------------------------------------------------------------|-----------|---------------------------------------------------------------------------------------|-----------|
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/kilobits`` |`1000`     |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/kibibits``|`1024`     |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/megabits`` |`1000e2`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/mebibits``|`1024e2`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/gigabits`` |`1000e3`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/gibibits``|`1024e3`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/terabits`` |`1000e4`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/tebibits``|`1024e4`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/petabits`` |`1000e5`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/pebibits``|`1024e5`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/exabits``  |`1000e6`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/exbibits``|`1024e6`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/zettabits``|`1000e7`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/zebibits``|`1024e7`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/yottabits``|`1000e8`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/yobibits``|`1024e8`   |

### Information Storage

Units of bytes commonly represent the amount of stored information.

|Decimal Bytes                                                                            |Coefficient|Binary Bytes                                                                            |Coefficient|
|-----------------------------------------------------------------------------------------|-----------|----------------------------------------------------------------------------------------|-----------|
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/kilobytes`` |`1000`     |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/kibibytes``|`1024`     |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/megabytes`` |`1000e2`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/mebibytes``|`1024e2`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/gigabytes`` |`1000e3`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/gibibytes``|`1024e3`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/terabytes`` |`1000e4`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/tebibytes``|`1024e4`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/petabytes`` |`1000e5`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/pebibytes``|`1024e5`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/exabytes``  |`1000e6`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/exbibytes``|`1024e6`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/zettabytes``|`1000e7`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/zebibytes``|`1024e7`   |
|``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/yottabytes``|`1000e8`   |``doc://com.apple.foundation/documentation/Foundation/UnitInformationStorage/yobibytes``|`1024e8`   |

## Topics

### Accessing Predefined Common Units

[`bits`](/documentation/Foundation/UnitInformationStorage/bits)

The bits unit of information.

[`nibbles`](/documentation/Foundation/UnitInformationStorage/nibbles)

The nibbles unit of information.

[`bytes`](/documentation/Foundation/UnitInformationStorage/bytes)

The bytes unit of information.

### Accessing Predefined Binary Units

[`kibibits`](/documentation/Foundation/UnitInformationStorage/kibibits)

The kibibits unit of information.

[`kibibytes`](/documentation/Foundation/UnitInformationStorage/kibibytes)

The kibibytes unit of information.

[`mebibits`](/documentation/Foundation/UnitInformationStorage/mebibits)

The mebibits unit of information.

[`mebibytes`](/documentation/Foundation/UnitInformationStorage/mebibytes)

The mebibytes unit of information.

[`gibibits`](/documentation/Foundation/UnitInformationStorage/gibibits)

The gibibits unit of information.

[`gibibytes`](/documentation/Foundation/UnitInformationStorage/gibibytes)

The gibibytes unit of information.

[`tebibits`](/documentation/Foundation/UnitInformationStorage/tebibits)

The tebibits unit of information.

[`tebibytes`](/documentation/Foundation/UnitInformationStorage/tebibytes)

The tebibytes unit of information.

[`pebibits`](/documentation/Foundation/UnitInformationStorage/pebibits)

The pebibits unit of information.

[`pebibytes`](/documentation/Foundation/UnitInformationStorage/pebibytes)

The pebibytes unit of information.

[`exbibits`](/documentation/Foundation/UnitInformationStorage/exbibits)

The exbibits unit of information.

[`exbibytes`](/documentation/Foundation/UnitInformationStorage/exbibytes)

The exbibytes unit of information.

[`zebibits`](/documentation/Foundation/UnitInformationStorage/zebibits)

The zebibits unit of information.

[`zebibytes`](/documentation/Foundation/UnitInformationStorage/zebibytes)

The zebibytes unit of information.

[`yobibits`](/documentation/Foundation/UnitInformationStorage/yobibits)

The yobibits unit of information.

[`yobibytes`](/documentation/Foundation/UnitInformationStorage/yobibytes)

The yobibytes unit of information.

### Accessing Predefined Decimal Units

[`kilobits`](/documentation/Foundation/UnitInformationStorage/kilobits)

The kilobits unit of information.

[`kilobytes`](/documentation/Foundation/UnitInformationStorage/kilobytes)

The kilobytes unit of information.

[`megabits`](/documentation/Foundation/UnitInformationStorage/megabits)

The megabits unit of information.

[`megabytes`](/documentation/Foundation/UnitInformationStorage/megabytes)

The megabytes unit of information.

[`gigabits`](/documentation/Foundation/UnitInformationStorage/gigabits)

The gigabits unit of information.

[`gigabytes`](/documentation/Foundation/UnitInformationStorage/gigabytes)

The gigabytes unit of information.

[`terabits`](/documentation/Foundation/UnitInformationStorage/terabits)

The terabits unit of information.

[`terabytes`](/documentation/Foundation/UnitInformationStorage/terabytes)

The terrabytes unit of information.

[`petabits`](/documentation/Foundation/UnitInformationStorage/petabits)

The petabits unit of information.

[`petabytes`](/documentation/Foundation/UnitInformationStorage/petabytes)

The petabytes unit of information.

[`exabits`](/documentation/Foundation/UnitInformationStorage/exabits)

The exabits unit of information.

[`exabytes`](/documentation/Foundation/UnitInformationStorage/exabytes)

The exabytes unit of information.

[`zettabits`](/documentation/Foundation/UnitInformationStorage/zettabits)

The zettabits unit of information.

[`zettabytes`](/documentation/Foundation/UnitInformationStorage/zettabytes)

The zettabytes unit of information.

[`yottabits`](/documentation/Foundation/UnitInformationStorage/yottabits)

The yottabits unit of information.

[`yottabytes`](/documentation/Foundation/UnitInformationStorage/yottabytes)

The yottabytes unit of information.


---

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