UUIDs (Universally Unique Identifiers) are codes designed to be unique across computer systems, like a universal “serial number”.
It is extremely unlikely for two UUIDs to be the same, even if they are generated on different systems at the same time.
You may have seen them somewhere before; they follow a format similar to this:
550e8400-e29b-41d4-a716-446655440000
(32 hexadecimal characters grouped as 8-4-4-4-12 and separated by hyphens)
In this video, I talk about a requirement that included this format and how to test it.