MS-DOS turns 30 Years Old Today!
On July 27, 1981, Microsoft purchased QDOS from Seattle Computer Products. It was a great deal.
When IBM came to Microsoft asking for a 16-bit operating system, the company had to scramble to get one together. Rather than writing a new one from the ground up, it turned to Seattle Computer Products and its existing 86-DOS (aka QDOS), and bought a non-exclusive license for $25,000. The next Spring, in May 1981, it hired away the program’s author, programmer Tim Paterson. And then, on July 27, it paid another $50,000 for all rights. A month later, it was shipping on IBM personal computers, and eventually turned Bill Gates and Paul Allen into two of the world’s richest men.