This stems from a question I had about nvarchar and varchar.
According to MSDN, varchar is:
...non-Unicode character data...
I've looked around for a clear definition of "non-unicode" but haven't had any luck. Is this the same thing as ASCII? If so, is there a reason that they don't just say ASCII?
No. It's not the same. LATIN1 is an example of a charset that's not UNICODE and is not ASCII either. Here is a list of charsets.
No, it is not the same thing and that's the reason why they didn't just say ASCII. There are many encodings out that are neither Unicode nor ASCII like Windows 1251 also known as CP1251 (cyrillic).