As a young teenager at Lakeside Prep School, Gates wrote his first computer program on a General Electric computer — it was a version of tic-tac-toe, where you could play against the computer.
Once his school realized Gates' proclivities for coding, they let him write the school's computer program for scheduling students in classes. He even slyly altered the code so he was placed in classes with a "disproportionate number of interesting girls."
Like many other successful tech entrepreneurs, Gates was a college dropout. He left Harvard University in 1975 to fully devote himself to Microsoft.
Gates was once arrested in New Mexico, in 1977. He was driving without a license and ran a red light.
He used to fly coach until 1997. Now, he has his own plane — he calls that his "big splurge."
One of Gates' biggest splurges, besides his plane, was the Codex Leicester, a collection of writings by Leonardo da Vinci. He acquired the codex at a 1994 auction for $30.8 million.
Despite his immense wealth, Gates says his kids will only inherit $10 million each — just a fraction of his $81.1 billion net worth. "Leaving kids massive amounts of money is not a favor to them," he says.
Gates doesn't know any foreign languages. That, he says, is his biggest regret in life thus far.
Gates scored a 1590 out of 1600 on his SATs.
Though he spends most of his time with his Foundation, Gates says he is still working with Microsoft on its "Personal Agent," which will "remember everything and help you go back and find things and help you pick what things to pay attention to."
Gates says if Microsoft hadn't worked out, he probably would've been a researcher for artificial intelligence.
But, despite his deep interest in AI, Gates says he is "in the camp that is concerned about super intelligence." That camp also includes notable leaders in science in technology, including Stephen Hawking and Elon Musk.
His favorite band? Weezer. He also calls U2 a "favorite," and says he's still "waiting for Spinal tap to go back on tour."