These are card decks containing source and object code. I was learning to program
and these were mostly just exercises in creating various types of files and retrieving
them. My programming wasn't much better than my spelling. The "20" on some decks
indicated that it was for the 360/20 rather than a "regular" 360. The model 20 instruction
set was pretty much a subset of the other machines with some special variations thrown
in to handle the 16 bit (instead of 32 bit) registers, etc.