🎲 UUID v4 (Random)
Generated from random numbers. Most commonly used. 128-bit
identifier with extremely low collision probability.
⏰ UUID v1 (Time-based)
Based on timestamp and MAC address. Guarantees uniqueness across
time. Useful for distributed systems.
🔧 Use Cases
Database primary keys, API request IDs, session tokens,
distributed system identifiers, and unique resource identifiers.
📊 Format
Standard format: 8-4-4-4-12 hexadecimal digits. Example:
550e8400-e29b-41d4-a716-446655440000