GUID (or UUID) is a short form for 'Globally Unique Identifier' (or 'Universally Unique Identifier'). This unique value is 128-bit integer number and used for identifying a resource. Generally, The term GUID is generally used by programmers working with Microsoft technologies. GUIDs are widely used in Microsoft products to identify interfaces, replica sets, records, and other objects.
UUID is 36 characters long represented as 32 hexadecimal (base 16) digits, presented in five groups separated by hyphens, in the form 8-4-4-4-12. UUID is 128-bits is big and over 1,000,000,000 GUIDs are created per second, then the probability of duplicate for one year is only 50%. An example of GUID is '123e4567-e89b-12d3-a456-426655440000'.
GUIDs is a 128-bit integer (16 bytes) are used in enterprise software development. GUID is used as database keys in different programming languages. Also used in networks, component identifiers, COM programming or wherever a unique identifier is required.
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