Understanding UUIDs and GUIDs
A UUID (Universally Unique Identifier) is a 128-bit number used to identify information in computer systems. Because they are 128-bit, the number of possible UUIDs is incredibly large (2^128), making the probability of duplication virtually zero.
This means you can generate a UUID on one system and another on a different system without worrying about coordination or a central database to prevent duplicates. This property is crucial for distributed systems and modern databases like MongoDB, Cassandra, or PostgreSQL.
Why Version 4?
There are 5 versions of UUIDs. This tool generates Version 4, which is based on random numbers.
- Version 1: Date-time & MAC address (Trackable, privacy risk).
- Version 3 & 5: Namespace-based (MD5/SHA1 hashing).
- Version 4: Random (Recommended for most use cases).
Fact: If you generated 1 billion UUIDs every second for the next 85 years, the probability of creating a single duplicate would be about 50%.