# UUID (data type)

A datatype representing a Universally Unique Identifier encoded as a 128-bit integer.

Note: In SNOMED CT release files *UUIDs* are represented as a string following the standard canonical form. In this string form a *UUID* is represented by 32 hexadecimal digits, displayed in five groups separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters (32 digits and four hyphens).

Example: ac527bed-9c70-4aad-8fc9-015828b148d9

## Related Links

* <http://en.wikipedia.org/wiki/Universally_unique_identifier>

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