The founder of Tesla and SpaceX says his passion for gaming inspired him to create his first companies.

Elon Musk surpassed Mark Zuckerberg last week to become the third richest person in the world. His fortune has grown rapidly since Tesla shares were added to the S&P 500 index.

Elon Musk now runs Tesla and SpaceX, with major projects such as battery-powered cars, sending people to space and even mining Mars. However, the billionaire’s roots lie in the technology industry. He founded X.com, the predecessor to PayPal. The money Musk earned from selling PayPal helped him fund Tesla.

Elon Musk and Peter Thiel, co-founders of X.com, which later became PayPal. Photo: AP.

In a talk with astronomer Neil DeGrasse Tyson, Elon Musk admitted that gaming was what sparked his passion for computers.

“My dad took me to the US when I was 10 years old. I remember it was a great experience because every hotel had a game console. When I went to a new hotel, I always went to the game console first,” Musk shared. At that time, he was still living with his family in South Africa.

“Playing games was really engaging, and that made me want to learn computer programming. I thought, I can make my own games. I wanted to figure out how games work and create new ones. That’s why I started learning programming,” the billionaire added.

Musk’s family owned a Magnavox Odyssey, the first home game console.

“It had four games, and that was it. Then there were Atari and Intellvision. One day I went to the store and saw the Commodore VIC-20. I was really surprised that I could own a computer and make my own games,” Elon Musk recalled.

Musk spent all his savings, begged his parents to buy the Commodore VIC-20 computer. The machine only had 5KB of RAM and 3.5KB of memory for programming. Still, it was more than enough for young Elon Musk.

Elon Musk’s passion for programming came from games.

“The computer had a BASIC programming manual. I stayed up all night reading it, almost obsessed with it. The first time you program, you realize how cool it is. You just type a few commands and the screen responds. It’s really cool,” Elon Musk recalled.

At age 12, after learning BASIC programming, Musk sold his first game to a magazine for $500. Eleven years later, Musk and his brother founded Zip2, a company that provided maps and local guides to newspapers. Musk said he was the main programmer for Zip2.

In 1999, the brothers sold the company to Compaq for $307 million. The money was used to found X.com. In 2002, the company, by then renamed PayPal, was sold to eBay for $1.5 billion.

After the deal, Elon Musk had both money and fame. That advantage helped him enter the electric car and space industries.

He said he still plays games recently. Musk’s favorite games include the strategy building game Civilization, Warcraft and the shooting game BioShock.