Bill Gates

Software developer and entrepreneur · Software developer · Entrepreneur · Philanthropist · Author

b. 1955 · Born in Seattle, Washington, United States · 4 min read

Last verified: 12 November 2026
Sources: 8
Reviewed by Muse — Phase C second review (independent check)

Bill Gates at the World Economic Forum Annual Meeting, Davos, 26 January 2012, by the World Economic Forum (photo: Sebastian Derungs) / Wikimedia Commons, licensed under CC BY 2.0 (https://creativecommons.org/licenses/by/2.0). Cropped to 3:4 portrait format for display; no other changes. · Licence: CC BY 2.0 · Source: https://commons.wikimedia.org/wiki/File:BillGates2012.jpg

American software developer and entrepreneur who co-founded Microsoft with Paul Allen in 1975 and later became one of the world's leading philanthropists through the Gates Foundation.

Early Life

William Henry Gates III was born on 28 October 1955 in Seattle, Washington, the only son of Bill Gates Sr., a lawyer, and Mary Maxwell Gates, a business executive. He attended Lakeside School in Seattle, where he met Paul Allen, and where the two formed a group of student programmers who computerised the school's payroll system and founded Traf-O-Data, a small company selling traffic-counting systems to local governments. Gates wrote his first software program at the age of 13.

Education

Gates enrolled at Harvard University in 1973. In 1975, while still a sophomore, he and Paul Allen developed software for the Altair 8800 microcomputer. He left Harvard during his junior year to found Microsoft with Allen, and did not complete a degree.

Career

In 1975 Gates, then a sophomore at Harvard University, joined his school friend Paul Allen to develop a version of the BASIC programming language for the Altair 8800, the first microcomputer. With that success Gates left Harvard during his junior year and, with Allen, formed Microsoft, founded on 4 April 1975 in Albuquerque, New Mexico. Microsoft licensed its MS-DOS operating system to IBM for the IBM PC, released in 1981, and retained the right to license it to makers of IBM-compatible computers, which made MS-DOS the standard. Windows followed in 1985, and Microsoft went public on 13 March 1986. Gates led the company through the rise of the internet in the 1990s, refocusing it on internet software from 1995. He stepped down as chief executive in 2000, when Steve Ballmer succeeded him, relinquished day-to-day oversight in June 2008 to devote himself to the Gates Foundation, stepped down as chairman in February 2014 and left the Microsoft board in 2020. He remains chair of the Gates Foundation and works on global health, climate and education, and published his memoir Source Code: My Beginnings in February 2025. In June 2026 he testified voluntarily before the US House Oversight Committee about his past association with Jeffrey Epstein, telling the committee that meeting Epstein had been 'a grave error in judgment' and that he had never witnessed criminal conduct; in August 2026 he discussed in a CNN interview an essay he had written warning about the risks of rapidly expanding artificial intelligence.

Achievements

Gates's first achievement was to put software at the centre of the personal computer. With Paul Allen he founded Microsoft in 1975 to write software for the Altair 8800, then licensed MS-DOS to IBM for its first personal computer in 1981, a deal that made Microsoft's operating system the industry standard. Windows, released in 1985, carried that position into the graphical era, and Microsoft's public offering in 1986 made the company one of the largest software businesses in the world. His second career has been philanthropy. The foundation he created with Melinda French Gates funds work on global health, including vaccines and the fight against polio and malaria, and on education and development. In 2010 he and Warren Buffett launched the Giving Pledge, and in May 2025 he announced that the Gates Foundation would spend $200 billion over the next two decades and wind down by 2045. He was awarded the Presidential Medal of Freedom in 2016.

Legacy

Gates is likely to be remembered in two parts: as the programmer-entrepreneur whose operating systems put a computer on most of the world's desks, and as the philanthropist who redirected a large part of that fortune into global health and development. Microsoft's MS-DOS and Windows made personal computing a mass activity, and the Gates Foundation became one of the largest private funders of work on vaccines, malaria, polio and education. His 2025 announcement that the foundation will spend $200 billion over twenty years and close by 2045 set a fixed end date on that philanthropic project.

Major Achievements

Co-founded Microsoft with Paul Allen on 4 April 1975, building software for the Altair 8800 microcomputer
Licensed MS-DOS to IBM for its first personal computer in 1981, making Microsoft's operating system the industry standard
Released Windows 1.0 in 1985, the start of the graphical operating system that became the world's most widely used
Took Microsoft public on 13 March 1986; served as chief executive until 2000, chairman until 2014 and a board member until 2020
With Melinda French Gates, created the foundation that became the Gates Foundation, funding global health, development and education programmes
Launched the Giving Pledge with Warren Buffett in 2010, a public campaign for wealthy people to commit most of their wealth to charitable causes
Awarded the Presidential Medal of Freedom in 2016
Author of The Road Ahead (1995), Business @ the Speed of Thought (1999), How to Avoid a Climate Disaster (2021) and Source Code: My Beginnings (2025)
In May 2025 announced the Gates Foundation would spend $200 billion over the next two decades and wind down operations by 2045

Contributions

Gates's contribution to computing was to treat software, not hardware, as the valuable part of a personal computer. By licensing MS-DOS to IBM while keeping the right to sell it to other manufacturers, he made Microsoft's system the standard for the whole industry, and Windows then carried personal computing into the graphical era. In philanthropy, the foundation he created with Melinda French Gates became a major funder of global health work, including vaccine programmes and the campaign against polio, and of education and development. The Giving Pledge, launched with Warren Buffett in 2010, extended that model by asking other wealthy people to commit most of their wealth to charitable causes.

Notable Works

The Road Ahead (1995)
Business @ the Speed of Thought (1999)
How to Avoid a Climate Disaster (2021)
Source Code: My Beginnings (2025)

Milestones

1955 — Born on 28 October in Seattle, Washington Source: Encyclopaedia Britannica; Wikipedia
1968 — Wrote his first software program at age 13 Source: Encyclopaedia Britannica
1973 — Enrolled at Harvard University Source: Encyclopaedia Britannica; Wikipedia
1975 — Co-founded Microsoft with Paul Allen on 4 April in Albuquerque, New Mexico Source: Encyclopaedia Britannica; Wikipedia
1975 — Left Harvard during his junior year to build Microsoft Source: Encyclopaedia Britannica
1981 — Microsoft licensed MS-DOS to IBM for the IBM PC, released in 1981 Source: Encyclopaedia Britannica
1985 — Microsoft released Windows 1.0 on 20 November Source: Wikipedia
1986 — Microsoft held its initial public offering on 13 March Source: Wikipedia; Goldman Sachs
1994 — Married Melinda French Gates and launched the William H. Gates Foundation Source: Encyclopaedia Britannica
1995 — Refocused Microsoft on the internet; published The Road Ahead Source: Encyclopaedia Britannica
2000 — Stepped down as Microsoft chief executive; the Bill & Melinda Gates Foundation was formed Source: Encyclopaedia Britannica; Wikipedia
2008 — Relinquished day-to-day oversight of Microsoft to focus on the Gates Foundation Source: Encyclopaedia Britannica
2010 — Launched the Giving Pledge with Warren Buffett Source: Encyclopaedia Britannica
2014 — Stepped down as Microsoft chairman; remained a board member until 2020 Source: Encyclopaedia Britannica
2016 — Awarded the Presidential Medal of Freedom Source: Encyclopaedia Britannica
2025 — Published the memoir Source Code: My Beginnings; announced the Gates Foundation's twenty-year, $200 billion spending plan and 2045 wind-down Source: Encyclopaedia Britannica
2026 — Testified voluntarily before the US House Oversight Committee about his past association with Jeffrey Epstein (2011-2014), telling the committee the association had been 'a grave error in judgment'; published an essay warning about the risks of rapidly expanding artificial intelligence Source: CNN; AFP (via BSS News)

Timeline

28 October 1955
Born William Henry Gates III in Seattle, Washington
Source: Encyclopaedia Britannica; Wikipedia
1968
Met Paul Allen at Lakeside School in Seattle
Year only — exact date unknown Source: Wikipedia
1973
Enrolled at Harvard University
Year only — exact date unknown Source: Encyclopaedia Britannica; Wikipedia
4 April 1975
Co-founded Microsoft with Paul Allen in Albuquerque, New Mexico
Source: Encyclopaedia Britannica; Wikipedia
1975
Left Harvard during his junior year to build Microsoft
Year only — exact date unknown Source: Encyclopaedia Britannica
1981
Microsoft licensed MS-DOS to IBM for the IBM PC
Year only — exact date unknown Source: Encyclopaedia Britannica
20 November 1985
Microsoft released Windows 1.0
Source: Wikipedia
13 March 1986
Microsoft held its initial public offering
Source: Wikipedia; Goldman Sachs
1994
Married Melinda French Gates; launched the William H. Gates Foundation with her
Year only — exact date unknown Source: Encyclopaedia Britannica
2000
Stepped down as Microsoft chief executive; the Bill & Melinda Gates Foundation was formed
Year only — exact date unknown Source: Encyclopaedia Britannica; Wikipedia
2008
Relinquished day-to-day oversight of Microsoft to focus on the Gates Foundation
Year only — exact date unknown Source: Encyclopaedia Britannica
2010
Launched the Giving Pledge with Warren Buffett
Year only — exact date unknown Source: Encyclopaedia Britannica
2016
Awarded the Presidential Medal of Freedom
Year only — exact date unknown Source: Encyclopaedia Britannica
2020
Left the Microsoft board
Year only — exact date unknown Source: Encyclopaedia Britannica
2021
Divorced Melinda French Gates
Year only — exact date unknown Source: Encyclopaedia Britannica; Wikipedia
2025
Published the memoir Source Code: My Beginnings
Year only — exact date unknown Source: Encyclopaedia Britannica
2025
Announced the Gates Foundation would spend $200 billion over twenty years and wind down by 2045
Year only — exact date unknown Source: Encyclopaedia Britannica
10 June 2026
Testified voluntarily before the US House Oversight Committee about his past association with Jeffrey Epstein, telling the committee that meeting Epstein had been 'a grave error in judgment' and that he had never witnessed criminal conduct
Source: CNN; AFP (via BSS News)
2026-08
Discussed in a CNN interview an essay he had written warning about the dangers of rapidly expanding artificial intelligence
Approximate date Source: LADbible (CNN interview)

In Their Words

“Success is a lousy teacher. It seduces smart people into thinking they can't lose.” Source: The Road Ahead (1995) — From The Road Ahead (1995), quoted in Encyclopaedia Britannica's profile of Gates.

Frequently Asked Questions

Who is Bill Gates?

Bill Gates (born 28 October 1955 in Seattle, Washington) is an American software developer and entrepreneur who co-founded Microsoft with Paul Allen in 1975. He later became a leading philanthropist as chair of the Gates Foundation.

Source: Encyclopaedia Britannica; Gates Foundation

How did Bill Gates start Microsoft?

Gates and his school friend Paul Allen founded Microsoft on 4 April 1975 in Albuquerque, New Mexico, to write software for the Altair 8800 microcomputer. Their first product was a version of the BASIC programming language for the machine.

Source: Encyclopaedia Britannica; Wikipedia

What made Microsoft successful?

In 1981 Microsoft licensed its MS-DOS operating system to IBM for the IBM PC, while keeping the right to license it to other manufacturers. Windows, released in 1985, then became the dominant graphical operating system for personal computers.

Source: Encyclopaedia Britannica

What does the Gates Foundation do?

Gates and Melinda French Gates created the foundation that became the Gates Foundation, which funds global health, development and education programmes. In 2010 Gates and Warren Buffett launched the Giving Pledge, and in May 2025 Gates announced the foundation would spend $200 billion over twenty years and wind down by 2045.