What is UUID?

A UUID (Universally Unique Identifier) is a 128-bit value used to uniquely identify information without a central authority. It is usually written as 32 hexadecimal digits in five groups, e.g. 550e8400-e29b-41d4-a716-446655440000.

Version 4 UUIDs are random and the most common; version 1 is time-based. Collisions are astronomically unlikely, which makes UUIDs ideal for database keys and distributed systems.