I ran my own blog from November 2006 till October 2014. All posts are still online, but I don't have time to update it anymore. Please note that all images and media files have been removed when the backup was moved to a new host in early 2016. Enjoy!

The Man Who Allowed Bill Gates To Become The Richest Man In The World

2. december 2007

Most of you probably never heard of Gary Kildall. Maybe that's due to a single bad decision Gary made - if he decided otherwise he might be a rich and famous man today, and nobody would know about a certain Bill Gates.

Gary Kildall, born in 1942, was a computer scientist, pioneer and entrepreneur. In 1973 he he developed the first high-level programming language for microprocessors, called PL/M, as well as one of the first operating systems for personal computers, called CP/M. He then created his own company, called Digital Research, to market his new OS.


To allow using CP/M on various hardware platforms, Kildall invented a method to implement hardware specific code in a single library - the BIOS concept was born. Within the next few years, the CP/M BIOS design allowed CP/M to became the most important operating system for computers. By 1981, at the peak of its popularity, CP/M ran on 3000 different computer models and DRI had $5.4 million in yearly revenues.

In 1980, IBM was designing it's new Personal Computer to challange the popular home computer systems Appleand other companies were offering. A small company called Microsoft was due to ship a BASIC interpreter for the upcoming IBM PC, and their founder Bill Gates suggested to license CP/M as standard OS for the new PC.

But then, Gary made a huge mistake. A meeting with IBM had been arranged, but Gary decided to deliver software using his private airplane and missed it.

Instead the IBM representatives met with Gary's wife Dorothy, who managed the company's business affairs. IBM requested the signature of a non disclosure agreement (NDA), but Dorothy refused this on the advice of her attorney. Apprently the IBM managers were frustrated about the results as they quickly needed an OS for their machine, they returned to Bill Gates and asked him to find another OS for them.

A few weeks later, Gates decided to license a CP/M clone from Seattle Computer Products (SCP). IBM shipped the CP/M clone as PC-DOS, and Microsoft shipped it as MS-DOS. So finally CP/M had made it to the IBM PC, but Gary Kildall and his Company Digital Research didn't have any influence on he future development anymore. Instead, it was Microsoft who became the most important OS company in the world, only by marketing a non-official CP/M clone under their own label.

And how did the story end? Digital Research's influence waned during the 1980's, and Novell acquired DRI in 1991 - a deal that made Gary a wealthy man, although he didn't have much time left to appreciate it. On July 8, 1994, Kildall sustained an injury at a Monterey restaurant and refused treatment. Three days later he died. The circumstances of the injury remaining unclear, an autopsy did not conclusively determine the cause of death.

In March 1995, Kildall was posthumously honored by the Software Publishers Association for his numerous contributions to the microcomputer industry and Bill Gates called him "one of the original pioneers of the PC revolution" and "a very creative computer scientist who did excellent work."