Hi all!
Are there various types of GUID? Can them be slimmer than '{6EB22381-
8AB9-12D0-81B7-00ABC9231C29}' and still be secure?

I would need them in a system where users enter GUIDs trought the Web
so as they get money credited to their account. What I have to assure
is that no type-mismatch or guessing GUIDs would give any other result
than 'Sorry, Non-existant Key'

Thanks, Marcelo.