It was 40 years ago today (April 7) that IBM announced to the world the first S/360 'mainframe' computer. There were other models prior to this, but the S/360 was the first to have a single unified archtecture definition from which all subsquent mainframes would be derived.
Consider that a program that was written and complied with the original S/360 Principles of Operation could still be run today - unmodified - on even the most current model (the z990) of 'mainframe' computer.
So hippy burpday to you both
