Bill Gates' next book is about how he became Bill Gates.

The billionaire Microsoft co-founder has already written several books on topics like business, technology, climate change and global health. A new memoir called "Source Code," which Gates announced in a blog post on Tuesday, will be the first to focus on his formative years — "from childhood through my decision to leave college and start Microsoft," he wrote.

Despite being "in the public eye since my early twenties," most people know very little about his early years, Gates wrote. The new book will explore "the relationships, lessons, and experiences that laid the foundation for everything in my life that followed," including building Microsoft into one of the world's biggest companies and deciding to donate "virtually all" of his estimated $128 billion net worth through his philanthropic foundation.

Gates, 68, called the memoir his "origin story" and promised to delve into aspects of his early life that could shed more light on the businessman he became. It'll publish in select countries on February 4, 2025. All proceeds from the book will go to the nonprofit United Way Worldwide, according to a spokeswoman for Gates.

"I share some of the tougher parts of my early life, including feeling like a misfit as a kid, butting heads with my parents as a rebellious teen, grappling with the sudden loss of someone close to me, and nearly getting kicked out of college," Gates wrote. "And I cover the challenges of dropping out of school to make a bet on an industry that didn't really exist yet."

Gates has shared some stories about his school-aged experiences before, and how they shaped his successful career. For instance, in a 2005 speech at Lakeside School — the private high school he attended in Seattle — Gates talked about how his experiences there helped shape him into a future tech titan.

"Lakeside was one of the best things that ever happened to me," Gates said. "One reason I'm so grateful to Lakeside is that I can directly trace the founding of Microsoft back to my earliest days here."

High school shaped Gates' future

Before enrolling at Lakeside, Gates wasn't sure he would like the school — and he nearly sabotaged his own admission.

"When I was in 6th grade, and my mom and dad suggested I go to Lakeside, I wasn't too sure about it," Gates said. "In those days, Lakeside was an all-boys school where you wore a jacket and tie, called your teachers 'master,' and went to chapel every morning. For a while, I even thought about failing the entrance exam."

Once there, Gates got an early introduction to computers — several faculty members managed to acquire a terminal, around the same time Gates started 7th grade in the late 1960s — and met his future Microsoft co-founder Paul Allen.

The machinery was new to everyone, students and faculty alike, Gates said. Computers cost thousands of dollars, they were slow and they consumed a lot of electricity. "That made computers seem pretty scary to some people here, especially when 13-year-old kids were eager to try their luck next," he said.

"The school could have shut down the terminal, or they could have tightly regulated who got to use it," said Gates. "Instead, they opened it up. Instead of teaching us about computers in the conventional sense, Lakeside just unleashed us."

Gates took to it quickly. He soon taught other students how to use computers, digitized the school schedule and hacked the scheduling system to be placed in all-girls classes.

"They could have hired an outside computer expert to do the scheduling system," Gates said. "Teachers could have insisted that they teach classes on computing, simply because they were the teachers and we were the students. But they didn't."

He credited his experience at the school to giving himself and Allen "the confidence to start a company based on this wild idea that nobody else agreed with — that computer chips were going to become so powerful that computers and software would become a tool that would be on every desk and in every home."

As a result, Gates added, "if there had been no Lakeside, there would have been no Microsoft."

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