It was BASIC, just one that had evolved quite far from really old school BASIC. I like to probably incorrectly think that AmigaBASIC (also written by MS) was a

It was BASIC, just one that had evolved quite far from really old school BASIC. I like to probably incorrectly think that AmigaBASIC (also written by MS) was a bit of a half way point between old 8bit BASIC and VB. It did away with line numbers, got a bit more event driven, and added a lot of GUI stuff like mouse handling, windows, menus etc etc etc.