Chibi-sama666

This may sound noob-ish, but I was wondering if anyone could explain what "Type 1, Type 2, etc." mean when using the built-in PID generator. I know they have something to do with what type the PID is (Normal NDS or GBA, Very Rare GBA, Common GBA Event (Unrestricted), etc.), but I was hoping to find out which number type corresponded to what. I've been searching around for a day or so looking for the information, but I can't seem to find it.