There is a baseline SQL standalone language that no one ever uses by itself.

Structured Query Language (or SQL) is its own thing independent of T-SQL and PL/SQL for Oracle (the PL is for Procedural Language) which sort of extend it to make their own flavors. Naturally, no one uses SQL standalone, so it was easy for me to think T-SQL and PL/SQL were just two similar ways of doing the "same" thing. I had an interview at Gimmal in this latest round of job hunting in which I was asked an interview question about the types of joins in SQL and I started speaking to the types of joins in T-SQL and the guy doing the interview straightened me out.