Yes - everyone seems to forget that S-100 CP/M business machines had been around since 1976. It wasn't a huge market, but it definitely wasn't negligible. And t

Yes - everyone seems to forget that S-100 CP/M business machines had been around since 1976. It wasn't a huge market, but it definitely wasn't negligible. And there were some home users, although most preferred Apple. So IBM didn't invent the PC. IBM invented mass marketing for its own brand of PC. And also - after a while - IBM started the constant upgrade treadmill. S-100 was more backward looking. You could get 8086 and 68000 cards for S100, but it was really a Z80 ecosystem. There was no clean upgrade path with backward compatibility. This was a showstopper for most businesses, which needed access to old data and software. IBM screwed themselves by hugely overcharging for PS/2, and Compaq stole their lunch. As soon as other clones appeared IBM were out.