The history of technology is full of surprises, sharp turns. Victories and defeats, betrayal and fidelity. Sometimes, to succeed, you just had to be in the right place at the right time. Or take friendly advice.

Today we will tell you about a man who could be a multi-billionaire, a celebrity of the level of Bill Gates, if he had a little more luck in his life. This man's name was Gary Kildall.

You may not know this name, but with a high degree of probability you saw or even used its brainchild - the CP/M operating system. It is almost unknown to the modern PC user, but at one time this OS was widely used on dozens of different machines, including ZX Spectrum (and its CIS clones), Robotron and the “proprietary” Commodore 128 (thanks to the Zilog Z80 as an on-board coprocessor). Many of those who used a computer running CP/M in those years did not even think where it came from.

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The early years

Kildall's career began in Monterey, California. He taught mathematics at the naval graduate school. His penchant for exact sciences pushed him to programming. Oddly enough, the reason for such a sharp change in activity was in advertising. Kildall caught sight of the announcement of the sale of a four-bit "microcomputer" based on Intel 4004. For only $ 25, he purchased the device. The potential of the machine was small, initially the microprocessor 4004 was supposed to be used in calculators, but it was enough for Kildall to immerse himself in computers and even meet with the creators of the processor.

Already in 1972, he defended his doctoral dissertation in computer science and got a job as an Intel consultant. High-quality academic education, a love of complex tasks and an entrepreneurial spirit allowed Kildall to achieve remarkable results as soon as possible.

According to eyewitnesses, he was a passionate lover of computers and once decided to teach his son programming on LOGO. There was no suitable interpreter at hand, and Kildall wrote it himself.

In the early 1970s, Kildall developed the PL/M programming language, Programming Language for Microcomputers. It was based on PL/1, which was quite popular in those years. It was assumed that the "high-level" code of the program was initially written on the mainframe a la IBM-360, and then translated into machine codes of the desired processor. Later versions of PL/M were already contained in the Intellec-4 ROM, Intel's first computer.

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Another noteworthy idea of ​​Kildall that came to him during the years of cooperation with Intel was to include in the “kit” of the microcomputer with the Intel 8008 (Intellec-8) not only a monitor, keyboard and punch reader, but also a Shugart floppy disk drive. Together with a university friend, Kildall in 1973 developed and successfully applied a drive controller. By the way, according to one version, it’s the witty Kildall that we owe the appearance of the word “floppy drive.”

Development and fate of CP/M

In the 1970s, software for computers was developed individually. It is easy to guess that such an approach could not but annoy the enterprising and ambitious programmer. Thanks to some technical refinements, Intellec-8 became much more convenient in operation, however, in order to turn it into a full-fledged machine, an operating system was required. The basis was the previous development - PL/M.

Kildall put cross-platform and widespread use of once written software at the forefront. And he didn’t try to compete with anyone: in those years, microprocessors were used primarily to control technology, and the idea of ​​building a full-fledged computer on them seemed new and interesting. Intel’s position seems very strange: they gladly bought PL/M from Kildall, and they remained completely indifferent to CP/M. Perhaps because they did not expect their Intellec-8 to gain enough popularity to make the purchase profitable.Intel went their own way and firmly occupied the microprocessor production market, and Kildall decided to continue working on the OS and sell it independently.

Kildall's contemporaries write that one of the factors that predetermined his future fate was age. On average, he was 10-15 years older than many of those we now know as the founding fathers of the PC era. He was knocked out of his generation, but could not find like-minded people among the “youth.”

Together with his wife, Dorothy, in 1976 he opened the company Intergalactic Digital Research. Despite such a big name, at first the staff consisted of only two people, and the “head office” was located in the Kildalls house in California. In 1977, the company was renamed Digital Research Inc. (DRI).

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Gary Kildall and his wife Dorothy

It was a huge success. Copies of CP/M diverged faster than hot cakes, and Kildall’s company was even accused of monopoly. By the end of the 1970s, microcomputers of the largest market players were using CP/M with might and main. Among them were IMSAI 8080, North Star and Osborne. It is noteworthy that at the same time, the small company of Bill Gates and Paul Allen's Traf-O-Data, which collected traffic data on the roads, also actively used CP/M. According to some reports, by 1980, more than 250 thousand copies of CP/M were sold.

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IMSAI is worth mentioning separately. In those years, this company almost exclusively exclusively supplied Altair’s clones to the market. In 1977, they acquired a CP/M license from Kildall, and this further contributed to its distribution on the market. Kildall inevitably flourished, became wealthy, and developed its operating system. So, it was in CP/M that preemptive multitasking was first introduced, and a dedicated BIOS appeared. Many Kildall-developed algorithms and principles in one form or another are still used today.

CP/M on the Altair 8800

Meanwhile, the era of microcomputers was drawing to a close. They gradually began to be replaced by personal computers. It all started with Apple I, which in 1976 was released by Steve Wozniak and co. In just three years, the PC market "bloated" to a billion dollars, and IBM finally appeared on the scene.

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The management of one of the largest technical companies in the United States understood very well: the market belongs to the young, and the only way to win is to give users something holistic, fast and convenient. Gates, who was on a short footing with many influential IBM people, recommended that they pay attention to the OS of Gary Kildall, because at that time Microsoft had only plans to create its own OS. Management IBM and Microsoft, however, signed a non-disclosure agreement, according to which Microsoft employees did not even have the right to mention IBM in a conversation.

At the beginning of the article we wrote: sometimes it’s just worth it to be at the right time in the right place. We’ll tell you one of the legends that indirectly explains the “death” of CP/M and the elevation of MS-DOS. True or not, it cannot be reliably said. Each of the parties interprets the story in its own way, so it will be easier to accept reality, rather than speculate about how the world could be if the other side won.

According to legend, Gates called Kildall and in a conspiratorial whisper said that in the coming days he should expect Very Important Guests. For a Very Important Talk. Directly saying that IBM were going to make him an offer of the century, he could not. The NDA did not even allow mention of the end customer.Gates sincerely believed that the sophisticated Kildall would understand who it was. But, apparently, Gary reacted to the words of a colleague with skepticism. Therefore, on the day when guests from IBM were at the doorstep of his house, he calmly flew in a private plane, entrusting all matters to his wife.

Dorothy and the DRI Legal Department met the visitors and presented CP/M as best they could. One way or another, they failed to impress or at least interest IBM. The story ended with the wife of Kildall and his employees also having to sign an unpleasant non-disclosure agreement, and the deal itself fell through. True, Kildall himself at that time did not have a 16-bit version of CP/M, so he could not fully satisfy IBM.

This is where Microsoft's finest hour came. Shrugging his shoulders, Bill Gates seized on this opportunity. Yes, his company still did not have its own OS at that time. But this did not mean at all that it was worth losing such a jackpot. Partly due to his own merits, partly due to his mother’s connections, Bill Gates received a contract to supply an operating system for the first IBM personal computer.

Gates, in turn, turned to Seattle Computers, releasing a Kildall OS clone. The company's founder, Tim Paterson, developed his own version of CP/M - 86-DOS. As he said later, to copy the original CP \ M, it was enough to copy the API calls from the official documentation, so he did not commit anything illegal. The system had a lot of bugs and deficiencies, so on the internal slang it was called Q-DOS (Quick and Dirty Operating System). The system was "renamed" in PC-DOS and presented by IBM. Subsequently, MS-DOS, known to all readers, was created on its basis. You can read more about the intricacies of intrigue around CP/M and Bill Gates in this article .

Gary was furious. Due to his own carelessness, he missed a brilliant opportunity to climb the Olympus of the world of personal computers. Even God bless him, with Olympus - instead of waiting and honestly buying a 16-bit version of the OS from him, Microsoft turned to its direct competitors.

IBM, anticipating the seething scandal over copyright, acted wisely. Both OSs were licensed to work with the IBM PC: PC-DOS and CP/M, and the winner was to choose the market.

Kildall's next rage came when IBM began touting their computers. According to the prices indicated in the advertisement, PC-DOS sold for $ 40, while CP/M Kildall from official distributors already cost $ 240. According to rumors, the sixfold difference in price was a deliberate attempt to “recall” Kildall how he did not appear at that fateful meeting.

In DRI, stagnation has begun. For some time, the company tried to stay, if not on a par, then walking not at two cases behind Microsoft. Kildall even developed his own graphical interface, GEM, however, on the eve of the release of Windows, Microsoft did not give him the opportunity to fully sell his designs.

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Kildall's life has changed dramatically after an unsuccessful contract with IBM. Over the next decade, the systems evolved in parallel and were compatible with each other, which was partly why DR-DOS (the new name CP/M since 1987) continued to sell. But in 1991, Windows 3.1 came out, which was no longer compatible with Kildall's DR-DOS. In just a year, sales slipped by an order of magnitude. In 1991, Kildall sold his Novell company, hoping to rebuff Microsoft under its wing. But this attempt failed: Novell DOS could no longer compete with MS-DOS and Windows.

Kildall’s life has a new companion - alcohol. He lost all his professional contacts and stopped appearing as a co-host on the popular TV program The Computer Chronicles, which he had been conducting for over 5 years.

Not much is known about the last months of Kildall's life. He was still more than a wealthy man.He owned a large collection of sports cars, real estate, but the interest and passion for the technology with which he lived for many years is gone.
In July 1994, at the age of 52, he died under mysterious circumstances during a fight in a biker bar. In 2016, with the permission of the children of Gary, was published part of his memoirs.


History has put everyone in their places. Someone is unknown and forgotten. Someone is the billionaire, philanthropist and most coveted secret Santa in the world.

Gary Kildall has done a lot to make computers the way we know them today. One of the great many people we would like to talk about on this blog.

You can not belittle the merits of talented people, even if they lost the war for the market. And in no case can you blame the winners for their failure.