© IBM/dpa

...Gates: After the leading software developer Gary Kildall from Digital Research did not take IBM's offer seriously, Gates seized the opportunity of a lifetime. Microsoft did not even have a suitable product in 1980. But Gates and his partner Paul Allen immediately recognized the prospects that an IBM contract would open up for them. Gates bought the core for a system software from a developer in the neighborhood for a paltry 25,000 dollars and licensed the conglomerate to IBM as PC-DOS 1.0. The experienced IBM managers even let Gates buy the rights to DOS and thus ensured that Microsoft was able to develop into a global software giant.

The triumphal march began.