Bill Gates
Bill Gates: Microsoft co-founder and software pioneer
Bill Gates is one of the major figures in the history of personal computing. As the co-founder of Microsoft with Paul Allen, he became involved in developing software for the first microcomputers during the 1970s. He quickly understood that software could become an industry independent of computer hardware.
Beginning with Altair BASIC, and later through the widespread adoption of MS-DOS and Windows, Microsoft became a central supplier of software for millions of personal computers. Bill Gates played several roles: programmer, business executive and commercial strategist. From the 2000s onward, he gradually reduced his responsibilities at Microsoft and devoted an increasing part of his time to philanthropy.
Quick facts
- Full name: William Henry Gates III
- Born: 28 October 1955, Seattle, Washington
- Fields: computing, software, entrepreneurship, philanthropy
- Main company: Microsoft
- Major contributions: Altair BASIC, development of Microsoft, widespread adoption of MS-DOS and Windows
First steps in programming
Bill Gates grew up in Seattle, Washington. In the late 1960s, he attended Lakeside School, where students gained access to a computer terminal connected to a remote computer. There he met Paul Allen, who shared his enthusiasm for programming.
At the time, access to computers was expensive and unusual. Gates and Allen spent a great deal of time learning how computers worked and writing their first programs.
They also worked on several commercial projects, including Traf-O-Data, a system designed to analyse data collected by road traffic counters.
In 1973, Bill Gates entered Harvard University, where he studied subjects including mathematics and computer science. He left Harvard in 1975 to devote himself to developing his young software company.
The Altair 8800 and the birth of Microsoft
In January 1975, Popular Electronics featured the Altair 8800 on its cover. The Altair was a microcomputer sold as a kit by a company called MITS.
Paul Allen and Bill Gates realised that these new machines would need accessible programming languages.
They contacted MITS and claimed to have a BASIC interpreter for the Altair. In reality, the program was not yet complete, and they did not even own an Altair 8800.
Development was carried out on a PDP-10 computer using a simulator that reproduced the behaviour of the Intel microprocessor used in the Altair.
Within a few weeks, Gates and Allen developed their interpreter. Paul Allen travelled to Albuquerque to demonstrate it. The program worked and became Altair BASIC, the first major commercial product of their future company.
In 1975, the two partners began using the name Micro-Soft, combining the words microcomputer and software. The hyphen was later dropped, and the Microsoft name was registered in 1976.
Turning software into a commercial product
Bill Gates was an early advocate of the idea that software had economic value in its own right. At a time when programs were frequently copied and exchanged among computer users, he argued that developers should be paid for their work.
In 1976, he published a letter that became known as the Open Letter to Hobbyists. In it, he criticised the unauthorised copying of Altair BASIC.
The letter generated considerable controversy within early microcomputer clubs, where sharing software was a common practice.
It illustrates an important transformation in the history of computing. Software was no longer merely something supplied with a machine or exchanged among specialists. It was gradually becoming a commercial product that could be developed and sold independently of computer hardware.
IBM, 86-DOS and the birth of MS-DOS
In 1980, IBM was preparing its first personal computer and approached Microsoft to provide programming languages for the new machine. IBM also needed an operating system.
Microsoft did not yet have a suitable operating system of its own. The company therefore turned to Seattle Computer Products, which had developed a system called 86-DOS.
86-DOS had been written by programmer Tim Paterson for computers based on Intel 8086 processors.
Microsoft first obtained a licence for 86-DOS and later acquired its rights. The system was adapted for the IBM PC and became PC DOS in the version distributed by IBM. Microsoft marketed its own version under the name MS-DOS.
Bill Gates therefore did not personally write MS-DOS from scratch. The system was directly derived from Tim Paterson’s work.
Microsoft’s crucial contribution was largely strategic and commercial: its agreement with IBM was not exclusive. Microsoft retained the right to supply MS-DOS to other computer manufacturers.
As IBM-compatible computers became increasingly common, MS-DOS gradually emerged as the standard operating system for this new family of machines.
This strategy placed Microsoft at the centre of the growing personal computer industry.
Windows and the spread of the graphical user interface
During the early 1980s, Microsoft developed a graphical environment intended to run on top of MS-DOS. The project was announced in 1983 under the name Windows.
The first commercial version of Windows was released on 20 November 1985. It provided support for a mouse, windows, menus and graphical applications.
However, this first version remained limited and was not immediately a major commercial success.
The situation changed with Windows 3.0 in 1990 and Windows 3.1 in 1992. These versions improved the graphical interface, memory management and graphical capabilities. They also benefited from the enormous growth of IBM-compatible personal computers.
In 1995, Microsoft launched Windows 95. Among its most visible innovations were the Start menu and taskbar. Windows 95 represented an important stage in bringing graphical interfaces to a mass audience of personal computer users.
At the same time, Microsoft developed numerous applications, including Word, Excel, PowerPoint and the Microsoft Office suite.
The combination of Windows and Office considerably strengthened Microsoft’s position in the personal computer market.
A highly effective business strategy
Microsoft’s success was not based solely on technical qualities. Bill Gates developed a strategy centred on distributing Microsoft software through as many computer manufacturers as possible.
Unlike Apple, which developed both its own computers and operating systems, Microsoft licensed its software to many companies producing IBM PC-compatible machines.
This approach allowed Windows to run on computers produced by numerous manufacturers.
Microsoft also encouraged developers to create applications for Windows. As the number of available applications increased, the platform became more attractive to users. More users, in turn, encouraged more developers to support Windows.
This reinforcing effect gradually strengthened Microsoft’s dominance of the PC software market.
The Microsoft antitrust case
Microsoft’s growing power also generated major criticism.
During the 1990s, the company integrated its Internet Explorer web browser into Windows, putting it in direct competition with Netscape Navigator, which was then one of the most popular browsers.
In 1998, the United States Department of Justice and several US states brought an antitrust case against Microsoft. They accused the company of using Windows’ dominant position to restrict competition in the web browser market and protect its monopoly.
In 1999, the court found that Microsoft possessed monopoly power in the market for operating systems for Intel-compatible personal computers and identified several anticompetitive practices.
In 2000, a judge ordered Microsoft to be split into two companies. This remedy was later overturned on appeal.
A settlement reached in 2001 ultimately imposed a number of restrictions on Microsoft.
The case demonstrates that Microsoft’s growth resulted from a combination of technical innovation, highly effective business strategy and practices that, at times, restricted competition.
Bill Gates was not the sole creator of Microsoft software
Unlike some technology executives, Bill Gates had genuine experience as a programmer. He directly participated in the development of Microsoft’s early software, including Altair BASIC.
It would nevertheless be incorrect to attribute all of Microsoft’s products to Gates alone.
Altair BASIC was developed with Paul Allen and other contributors. MS-DOS was derived from 86-DOS, written by Tim Paterson. Windows, Word, Excel and Microsoft’s other major products were created by large teams of engineers and programmers.
Bill Gates’ particular importance lies in his early understanding of the strategic value of software, his ability to negotiate licensing agreements and his role in building an ecosystem around Microsoft platforms.
The gradual transition to philanthropy
In January 2000, Bill Gates stepped down as Microsoft’s chief executive officer, with Steve Ballmer taking over the position.
Gates nevertheless retained major responsibilities within the company, including serving as chairman of the board and chief software architect.
That same year, Bill Gates and Melinda French Gates created the Bill & Melinda Gates Foundation by combining several earlier philanthropic organisations.
The foundation has focused primarily on global health, vaccination, infectious diseases, poverty reduction and education.
In 2008, Bill Gates left his day-to-day role at Microsoft to concentrate primarily on the foundation. He stepped down from Microsoft’s board of directors in 2020.
Melinda French Gates left the foundation in 2024. In 2025, the organisation officially became the Gates Foundation, with Bill Gates serving as its sole chair.
That same year, Gates announced his intention to give the vast majority of his fortune to the foundation. The organisation plans to spend approximately $200 billion more before ending its operations at the end of 2045.
Why Bill Gates is a major figure in computing history
- Software industry: he understood very early that software could be sold independently of computer hardware.
- Microcomputing: Altair BASIC helped make the first microcomputers easier to program.
- Standardisation: MS-DOS and later Windows became common platforms used by computers from many manufacturers.
- Software ecosystem: Microsoft encouraged thousands of developers to create applications for its platforms.
- Business strategy: licensing agreements with IBM and PC manufacturers contributed substantially to Microsoft’s success.
- Philanthropy: Gates has devoted a substantial part of his fortune to global health, education and poverty reduction.
- Controversies: Microsoft’s dominance led to one of the most important antitrust cases in the history of the computer industry.
Timeline
- 1955: Bill Gates is born in Seattle
- Late 1960s: discovers computer programming at Lakeside School
- 1973: enters Harvard University
- 1975: develops Altair BASIC and establishes Microsoft with Paul Allen
- 1976: Microsoft trademark is registered
- 1980: agreement with IBM to supply an operating system for its future PC
- 1981: IBM PC launches with PC DOS
- 1985: first commercial version of Windows is released
- 1986: Microsoft goes public
- 1990: Windows 3.0 is released
- 1995: Windows 95 is launched
- 1998: major US antitrust case against Microsoft begins
- 2000: Gates steps down as CEO and the Bill & Melinda Gates Foundation is created
- 2008: leaves his day-to-day role at Microsoft
- 2020: leaves Microsoft’s board of directors
- 2025: the Bill & Melinda Gates Foundation becomes the Gates Foundation
Cover photo: Bill Gates by © European Union, 2026, CC BY 4.0, Link
