UUID
Alternatively referred to as a GUID (Globally Unique IDentifier), UUID is short for Universal Unique IDentifier and is a 128-bit unique identification value. UUIDs are used in the Apollo Network Computing System, OSF (Open Software Foundation), DCE (Distributed Computing Environment), and Microsoft Windows, and is fully defined in RFC 4122. Below is an example of what a UUID may look like.
bc37d0c0-fcf2-11d9-8cd6-0800200c9a66
In the above example, the UUID has a timestamp of Monday, July 25, 2005 3:59:05 AM MDT. An online UUID generator can also be found at http://kruithof.xs4all.nl/uuid/uuidgen.
Also see: CLSID, DCE, Operating system definitions, URN