In the summer of 1980, IBM, the biggest computer company on Earth, asked a 24-year-old for an operating system he didn't have. Bill Gates found one across town, bought it, licensed it to IBM, and kept the right to sell it to everyone else. Today the company he co-founded brings in about 332 billion dollars a year and is worth about 3.9 trillion. How did that happen?

This 15-minute animated documentary starts in a Seattle school room in 1968, where two teenagers, Bill Gates and Paul Allen, met a teletype terminal. It follows the eight-week gamble on Altair BASIC in Albuquerque, the disputed IBM meeting with Digital Research, the $50,000 purchase of QDOS that became MS-DOS, and the license that let Microsoft own the standard while IBM built the hardware.

Then come Windows and the lawsuit with Apple, the 1986 IPO, the Internet Tidal Wave memo and the browser war with Netscape, and United States v. Microsoft, when a judge ordered the company to be broken in two. It covers the Ballmer years and the missed shift to mobile, Gates's move to philanthropy, Satya Nadella's turnaround with the cloud and Azure, and the OpenAI partnership, with the latest figures. The ending answers the title question with the four real reasons the empire was built.

Chapters 00:00 Intro 00:51 The Teletype Room 02:07 Eight Weeks to Albuquerque 03:47 The Deal of the Century 05:37 Windows and the War With Apple 07:13 The Tidal Wave 08:29 United States v. Microsoft 09:47 The Lost Decade 10:42 A Second Act 11:26 The Cloud 12:33 The AI Bet 13:58 How the Empire Was Built

Original 1080p30 animation with an AI voiceover, an original music score and sound design. Real people are shown as stylised illustrations. Fact-checked, with sources for every major claim; disputed accounts are attributed. Includes burned-in English subtitles and a 20-second end screen.