>identity
Identity does exactly that identifies, it has nothing to do with your real identity. I am not saying register your email, address, phone, etc…
Here is a short ex.
An id such as Superanon "maybe" hashed, to keep it short, as #!!dk5
now a salt based on a password "somepass" could be hashed to "&1jfl"
Put both together #!!dk5&1jfl could be a tripcode for "SuperAnon". length varies depending on alogorithms but can be truncated safely to 10 characters with a possibility of being the same is 1 in 130 million for example.
UUIDs work that way.