> For the complete documentation index, see [llms.txt](https://xoops.gitbook.io/xmf-cookbook/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://xoops.gitbook.io/xmf-cookbook/reference/uuid.md).

# Uuid

`Xmf\Uuid` can be used to generate UUIDs (Universally Unique IDentifiers)

A [UUID](https://en.wikipedia.org/wiki/Universally_unique_identifier) is a 128-bit number that serves as a unique identifier.

## Uuid::generate()

Returns a version 4 (random) UUID

## Uuid::packAsBinary($uuid)

Returns a packed version of the supplied UUID. The return is a 16 byte binary string, a compact form that may be more suitable for database storage.

## Uuid::unpackBinary($packedUuid)

Returns a full human readable UUID from the supplied packed form 16 byte binary string.