What does guid mean?

What does guid mean?

Globally Unique Identifier (GUID, Globally Unique Identifier) ​​is a numeric identifier with a binary length of 128 bits generated by an algorithm. GUID is mainly used in networks or systems with multiple nodes and multiple computers. Ideally, no computer or computer cluster will generate two identical GUIDs.

The total number of GUIDs reaches 2^128 (3.4×10^38), so the possibility of randomly generating two identical GUIDs is very small, but it is not 0. Therefore, the algorithms used to generate GUIDs usually add non-random parameters (such as time) to ensure that this repeated situation does not occur.

The term GUID sometimes refers specifically to Microsoft's implementation of the UUID standard.

On the Windows platform, GUID is widely used in Microsoft products to identify objects such as registry keys, class and interface identifiers, databases, and system directories.

Format

The format of the GUID is "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx", where each x is a ten in the range of 0-9 or a-f Hexadecimal number. For example: 6F9619FF-8B86-D011-B42D-00C04FC964FF is a valid GUID value.

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