Gary Kildall

Gary Kildall
Born	(1942-05-19) 19 May 1942 Seattle, Washington, U.S.
Died	11 July 1994(1994-07-11) (aged 52)
Occupation(s)	Computer scientist, entrepreneur
Known for	CP/M operating system, Digital Research, Inc., BIOS development, PL/M programming language, Computer Chronicles co-host

Gary Arlen Kildall (; May 19, 1942 – July 11, 1994) was a prominent American computer scientist and entrepreneur in the microcomputer industry. During the 1970s, he created the operating system CP/M along with several other operating systems and programming tools, subsequently founding Digital Research, Inc. to distribute his software products. He is widely acknowledged as a key figure in the personal computer revolution.

In 1974, Kildall showcased the initial functional CP/M prototype in Pacific Grove, California. This operating system later became a dominant platform for microcomputers for a time. His development of the BIOS (Basic Input Output System) was instrumental in allowing microprocessor-based machines to communicate with disk storage devices. Kildall was among the earliest to identify microprocessors as fully capable computing systems. In the 1980s, he co-hosted Computer Chronicles on PBS, a program dedicated to advancements in personal computing.

Early life

Born and raised in Seattle, Washington, Gary Kildall's family operated a school focused on seamanship. His father, Joseph Kildall, was a Norwegian-descended captain, while his mother Emma had Swedish roots, with Kildall's grandmother having emigrated from Sweden to Canada.

Education

Kildall completed a bachelor's degree in mathematics in 1967 and followed it with a master's degree in Computer Science in 1968 at the University of Washington. Initially planning to become a mathematics instructor, he redirected his career towards computer technology and pursued doctoral studies in Computer Science. To fulfill his military draft commitment, he taught at the Naval Postgraduate School located in Monterey, California, finishing his Ph.D. in 1972.

Intel supplied him with 8008 and 8080 microprocessors, which inspired him to create the first high-level programming language tailored for microprocessors—PL/M—in 1973. He also developed simulators for the 8008 and 8080 instruction sets called INTERP/8 and INTERP/80. That same year, he designed the operating system CP/M to allow the 8080 processor to manage floppy disk drives by integrating essential computer functions at the microcomputer level. Although Kildall demonstrated CP/M to Intel, they chose to prioritize marketing PL/M instead.

CP/M

In 1973, together with Kathryn Strutynski, Kildall created PL/M as part of their effort to develop CP/M, one of the pioneering operating systems for personal computers. Leveraging their background working with IBM mainframes and the VM operating system, they established "Intergalactic Digital Research" (which later became known as Digital Research, Inc.) to promote CP/M through hobbyist publications.

Digital Research licensed CP/M for use on the IMSAI 8080, a popular clone of the Altair 8800. As CP/M expanded its reach across multiple hardware platforms, Kildall introduced the BIOS concept—firmware stored on ROM or EPROM chips—that allowed CP/M to operate across various systems without requiring modifications.

Though CP/M rapidly became a widely accepted standard, Kildall was somewhat slow to adapt it for new technologies such as high-density floppy disks and hard disk drives. With mounting competition from hardware manufacturers creating alternative systems, he accelerated development of CP/M 2. By 1981, CP/M was compatible with approximately computer models and generated roughly million dollars annually for Digital Research.

Between 1983 and 1984, Digital Research packaged business and educational software for the IBM PC on bootable floppy disks alongside SpeedStart CP/M—a lightweight version of CP/M-86 designed as a bootable runtime environment.

IBM negotiations

In 1980, following a recommendation from Bill Gates, IBM initiated contact with Digital Research to discuss acquiring an upcoming version of CP/M called CP/M-86 for use on the IBM PC. Gary Kildall assigned his wife, Dorothy, to handle the initial discussions while he and Tom Rolander, responsible for developing the MP/M operating system, delivered software to manufacturer Bill Godbout. Prior to revealing their intent, IBM representatives requested Dorothy to sign a non-disclosure agreement, which she declined to do without Gary's consent. Gary later returned to continue negotiations; accounts vary on whether he signed the agreement or met with IBM personnel.

The reasons behind the unsuccessful negotiations are debated: Digital Research, possessing a limited product range, may have rejected IBM’s one-time payment proposal in favor of its usual royalty-based model. Dorothy might have questioned the feasibility of meeting IBM’s timeline due to ongoing PL/I development for Data General. IBM representatives may have been irritated by procedural delays. Kildall claimed additional discussions took place during a shared flight to Florida, culminating in a handshake deal. IBM negotiator Jack Sams denied having met Gary but acknowledged others might have been on the flight; Sams subsequently returned to Seattle for consultations with Microsoft.

Sams recounted these events to Gates, who had agreed to provide BASIC and other software for the PC. Gates perceived Kildall as having "gone flying" unpredictably. Sams assigned Gates the task of sourcing an operating system; within weeks, Gates presented 86-DOS, an independently created OS that replicated CP/M's API from Seattle Computer Products (SCP). Paul Allen secured licensing agreements with SCP, adapted 86-DOS for IBM hardware, and it was released as IBM PC DOS.

Upon reviewing PC DOS, Kildall believed it infringed on CP/M’s rights. Legal advisors indicated software intellectual property law was ambiguous regarding such cases. Kildall threatened legal proceedings; IBM responded by offering CP/M-86 as an optional OS for the PC if liability claims were waived. Kildall agreed but underestimated IBM’s impact on the PC market. At launch, IBM sold its OS choices separately: PC DOS was priced at , becoming indispensable due to software availability and limitations of built-in Cassette BASIC. CP/M-86 debuted months later at six times the cost (), suffered poor sales against DOS, and lacked sufficient software compatibility.

Multi-Programming Monitor Control Program (MP/M)

Following the collapse of the IBM deal, Gary and Dorothy recruited seasoned management personnel, which diminished Gary’s role within the company. He then concentrated on innovative projects such as MP/M, a multitasking variant of CP/M developed in 1979 by Digital Research’s Tom Rolander. Additionally, Kildall worked on implementing the Logo programming language intended to replace BASIC in educational settings; however, it did not achieve widespread acceptance.

FlexOS

In 1985, Digital Research introduced FlexOS, a modular real-time multitasking operating system designed for multiuser environments, targeting industrial and embedded applications.

Graphics Environment Manager (GEM)

Motivated by the Apple Lisa’s interface, Kildall spearheaded development of Digital Research’s graphical user interface named Graphics Environment Manager (GEM), which launched on February 28, 1985. Novell acquired Digital Research in 1991, yielding substantial financial returns for Kildall. Although he stepped down as CEO in June 1985, he continued serving as chairman of the board.

Computer Chronicles

Kildall served as a co-host on the PBS public television series Computer Chronicles, which focused on developments in personal computing. He was part of the hosting team for seven years during the program’s initial eight seasons, spanning from 1983 to 1990. The series itself continued airing until its 19th season, concluding in 2002.

Activenture

In 1984, Kildall established Activenture, a company dedicated to leveraging optical disc technology for computer applications, specifically utilizing the Red Book standard developed by Sony and Philips. The following year, Activenture underwent a rebranding and became known as KnowledgeSet.

The Electronic Encyclopedia

Digital Research launched The Electronic Encyclopedia in June 1985, offering a CD-ROM adaptation of Grolier's Academic American Encyclopedia. This marked the first instance of a computerized encyclopedia, which was later augmented with images in 1990 and enriched with audio and video features by 1992. Ownership of the encyclopedia eventually transferred to Banta Corporation, with its final CD-ROM edition released in 2003.

Prometheus Light and Sound (PLS)

Kildall’s last entrepreneurial effort was Prometheus Light and Sound (PLS), headquartered in Austin, Texas. The company developed a modular PBX system that integrated both land-line and mobile phone technologies—referred to as "Intelliphone"—aimed at lowering online communication costs and facilitating remote device connectivity.

This system incorporated a UUCP-based store-and-forward protocol to enable email and file transfers between nodes, with plans to support TCP/IP protocols in future iterations.

Computer Animation

Brian Halla, Intel’s liaison during the 1970s, recalled Kildall showcasing a spinning Coke bottle animation created on a VAX 11/780 computer at his home. This animation was subsequently sold by Kildall to Pixar.

Computer Connections

In 1992, Kildall received an invitation to attend the University of Washington’s computer science department's 25th anniversary event but felt slighted by being included solely as an attendee. He also expressed dissatisfaction that Bill Gates was selected as the keynote speaker despite not being an alumnus, though Gates had made donations to UW.

Motivated by these experiences, Kildall began composing his memoir titled Computer Connections: People, Places, and Events in the Evolution of the Personal Computer Industry, where he conveyed his disappointment regarding how software craftsmanship was undervalued.

Within his memoir, Kildall characterized Gates as "more of an opportunist than a technical type," noting that Gates held "strongly opinionated" perspectives that were sometimes unreasonable.

He described DOS as "plain and simple theft" due to its initial 26 system calls being nearly identical to those in CP/M, and accused IBM of manipulating pricing strategies between PC DOS and CP/M-86 to suppress CP/M’s market presence.

By late 1993, Kildall had completed a preliminary draft of this memoir, which has never been officially published. Journalist Harold Evans utilized this draft extensively for his 2004 book They Made America, concluding that Microsoft had appropriated Kildall’s innovations. However, some IBM insiders challenged this portrayal, while Microsoft dismissed it as "one-sided and inaccurate".

In August 2016, Kildall’s family made publicly available the first seven chapters of Computer Connections as a free download.

Personal life

During his high school years, Kildall identified as a greaser and was remembered by peers as imaginative, laid-back, and daring. His interests extended beyond aviation to include sports cars, auto racing, boating, and a lifelong affinity for the ocean.

Although Kildall chose to concentrate on his professional achievements rather than the IBM episode, media-driven comparisons to Bill Gates persisted, often fueled by stories claiming he missed a pivotal IBM meeting due to a leisure flight. In his later years, he expressed resentment over being eclipsed by Microsoft and faced challenges related to alcoholism.

The acquisition of Digital Research by Novell brought Kildall considerable wealth, enabling him to move to West Lake Hills in Austin. There, he owned a lakeside property equipped with garages for sports cars and a basement video studio. He piloted his personal Learjet and kept boats on the lake. Additionally, he dedicated time to volunteer efforts assisting children affected by HIV/AIDS. Kildall also maintained an ocean-view mansion in Pebble Beach, California, close to Digital Research’s main offices.

Death and legacy

On July 8, 1994, at 52 years old, Kildall suffered a head injury at the Franklin Street Bar & Grill, a biker establishment in Monterey, California. The exact details remain uncertain; accounts range from an accidental fall to potential assault linked to his Harley-Davidson attire. He was discovered injured inside the bar and discharged twice from medical care before passing away on July 11 at Community Hospital of the Monterey Peninsula.

The autopsy did not definitively establish the cause of death but identified that the head trauma led to a cerebral hemorrhage with a resulting blood clot. Medical findings also revealed chronic alcohol abuse. Initial inquiries explored the possibility of foul play or homicide; however, no conclusive determination was made.

Kildall was cremated, with his ashes laid to rest at Evergreen Washelli Memorial Park in Seattle.

Recognition

After Kildall’s passing, Bill Gates referred to him as "one of the original pioneers of the PC revolution," acknowledging his inventive spirit and significant industry contributions. Gates recognized their rivalry but conveyed profound admiration for Kildall’s achievements and mourned his premature death.

Stewart Cheifet, co-host of Computer Chronicles, called Kildall his "favorite guy," emphasizing his technical expertise and influence on personal computing. Cheifet observed that Kildall was "too much of a gentleman" and "a decent man in an industry where succeeding while being decent was difficult."

In March 1995, the Software Publishers Association (SPA) posthumously recognized Kildall for several groundbreaking accomplishments:

• Creation of the first microprocessor programming language and compiler: PL/M (1973)
• Development of CP/M, the first microprocessor disk operating system, which sold over 250,000 units (1974)
• Advancement of open system architecture by separating hardware interfaces through BIOS routines (1975)
• Innovations including diskette track buffering, read-ahead algorithms, directory caching, and RAM drive emulators
• Introduction of preemptive multitasking and windowing operating systems with Digital Research products such as MP/M, Concurrent CP/M, Concurrent DOS, DOS Plus, and GEM
• Development of a binary recompiler known as XLT86 (1981)
• Design of the first computer interface for video disks enabling nonlinear playback—anticipating interactive multimedia (1984, in partnership with Activenture)
• Engineering of file systems and data structures for the initial consumer CD-ROM (1985, alongside KnowledgeSet)

In April 2014, Pacific Grove dedicated a commemorative plaque at Kildall’s former home, which also served as Digital Research’s early headquarters.

In popular culture

Playwright Steve Hauk authored A Mild Concussion, which was subsequently updated in collaboration with Stewart Cheifet and retitled The Forgotten Computer Genius. This work portrays the concluding period in the life of a pioneering figure in computing.

See also

• History of personal computers

External links

• "Dr. Gary A. Kildall". MaxFrame Corporation. [1]
• "Eulogies for Gary Kildall by Eubanks, Pierce, Swain, Rolander, Spitz, Libes, and others". MaxFrame Corporation. [2]

Video