I think that was basically C, and POSIX. Except Microsoft wasn't particularly interested in it, and they thought they'd be better off if they didn't make their

I think that was basically C, and POSIX. Except Microsoft wasn't particularly interested in it, and they thought they'd be better off if they didn't make their software work for competing OS's. In a sense, most programs today are really portable. I think in the past, there was a far greater variety of machines, and people used to make programs for them specifically, in assembly, that absolutely wouldn't run on even a different generation of the same familly of machines.