@djsumdog @Ricotta I'm no expert on the history of Microsoft, but from what I've heard Paul Allen was probably more involved than Bill Gates and Bill just took all the credit. It's just another Steve Jobs/Steve Wozniak situation.
I wasn't even born yet at the time but I was told that had Commodore adopted the same business model as IBM/Microsoft (license their Amiga OS and architecture to other computer manufacturers), Microsoft would probably have never become a monopoly.
@xianc78 @Ricotta The PC was the first big open architecture product from IBM. They sourced parts rather than build everything in house in order to compete with Apple for workstations (even though Apple products themselves were fairly closed architecturally).