What is the purpose of system table master..spt_values and what are the meanings of its values?

Question

What is the purpose of system table master..spt_values?
Why was it provided and how one should use it?

What are the meanings of its type, low, high values?

Answer 1

Mostly answered in another question.

What are the meanings of its type, low, high values?

Most Types (ie. each specific lookup table, if they were separate) require either Name or Number. Some Types require Low and High columns as well. In Sybase, we have an ErrorNumber column, so the sproc can RAISERROR which is not hard-coded (can be changes with versions, etc).

It is not "cryptic" unless an enumerated list is "cryptic" to you; it is just a lookup table (all of them, differentiated by the Type column).