Development
What is UUID?
Universally Unique Identifier — a 128-bit label used to uniquely identify information in computer systems.
A UUID (Universally Unique Identifier) is a 128-bit value formatted as 32 hexadecimal digits in the pattern xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx. UUIDs are designed to be globally unique without requiring a central coordinator.
There are five UUID versions. UUID v4, the most commonly used, generates its value from random or pseudo-random numbers. The probability of generating two identical UUID v4 values is astronomically small (approximately 1 in 5.3 × 10^36).
Common Uses
- Database primary keys (avoiding sequential IDs)
- Session identifiers
- Distributed system correlation IDs
- API resource identifiers
- File naming to prevent collisions
FAQ
What is the difference between UUID and GUID?
GUID (Globally Unique Identifier) is Microsoft's implementation of UUID. They use the same format and are functionally identical.
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