Over the past two decades, Elon Musk has launched several multibillion-dollar companies such as PayPal, Tesla and SpaceX. His success as a serial entrepreneur, though, follows an eventful childhood in which a young Musk played with homemade rockets, coded his own video games and endured hardships both at school and home.
Here are eight things you might not know about Musk's youth.
While growing up in Pretoria, Musk, his brother Kimbal and their cousins traveled around the wealthy parts of the South African capital selling homemade chocolate Easter eggs.
The adventurous group traveled door-to-door, selling the sweets for 20 times the cost of making them.
"I'd make them for 50 cents and charge $10 for an Easter egg and I'd always get this question like, 'Why are you charging $10 for this little Easter egg?'" said Kimbal to CNBC Make It in a 2017 interview. "And I was like, 'Well, you're supporting a young capitalist. And the reality is if you don't buy it from me, you're not going to get one — and I know you can afford $10.'"
Musk has been open about his difficult childhood, discussing it most recently in last Sunday's "60 Minutes" interview. While he attended grade school in Pretoria, South Africa, Musk was not only the youngest and smallest kid in his class, but he was nerdier and much more into books than many jocks at school.
In Ashlee Vance's 2015 book "Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future, " Musk said gangs of boys at would sometimes hunt him down, going so far as to push him down a flight of stairs in one instance and send him to the hospital. "I was almost beaten to death," he added on "60 Minutes."
The bullying continued until he was 15 years old, when went through a growth spurt and learned how to defend himself by doing karate, judo and wrestling. By 16, he said he was "dishing it out as hard as they'd give it to me."
Musk was so introspective as a kid that his parents and doctors ordered tests to check if he was deaf. His mother Maye Musk eventually learned this was his way of daydreaming about his inventions.
"He goes into his brain and then you just see he is in another world. He still does that. Now I just leave him be because I know he is designing a new rocket or something," recalled Maye Musk in Vance's book.
Though this bothered his peers, who could reportedly yell at him and do jumping jacks beside him and he wouldn't notice, Musk's pensive moments allowed him to visualize projects he'd hope to tackle.
While his parents were away, Musk lived mostly under the watch of a housekeeper. According to Musk, she was mainly there to make sure he didn't break anything.
"She wasn't, like, watching me. I was off making explosives and reading books and building rockets and doing things that could have gotten me killed," said Musk. "I'm shocked that I have all my fingers."
Throughout his childhood, books played a crucial role in fueling Musk's ambitions and entertaining him. Said Musk, "I was raised by books. Books, and then my parents."
He reportedly read the entire Encyclopedia Britannica at age nine and would pore over science fiction novels, comics and nonfiction books for up to 10 hours a day. Some of the most influential books he read included "The Lord of the Rings," "The Hitchhiker's Guide to the Galaxy" and Isaac Asimov's "Foundation" series.
In the early days of computer coding, a 12-year-old Musk built a "Blastar, " a science-fiction-inspired space game. Similar to the classic "Space Invaders" arcade game, the objective in "Blastar" was to destroy an alien spacecraft carrying deadly bombs.
Although he's since called it a trivial game, "Blastar" earned Musk an easy $500 after a South African trade publication published its source code.
Along with his cousins, Musk loved playing the fantasy role-playing game. One time, the teens went to Johannesburg for a Dungeons & Dragons tournament.
"That was us being nerd masters supremes," Musk told Vance.
According to his cousin Peter Rive, Musk helped their team win the tournament with his "incredible imagination" and ability to keep people "captivated and inspired."
Along with his younger cousins and Kimbal, Musk got the idea to open an arcade by their high school, according to Vance's book. They got as far as signing a lease, setting contracts together filling out forms at the city planning department. But their plans were foiled when the city told them they were too young to get a real estate permit without an adult to sign off.
According to Kimbal, both his father and uncle "flipped out " when they brought up their arcade plans.
Once Elon reached his teens, he moved from his native South Africa to begin his college studies in North America. At 17, he first emigrated to "see what it takes to live," he told Neil DeGrasse Tyson on StarTalk Radio. Musk found that "in America, it's pretty easy to keep yourself alive."
Given that his threshold for existing was "pretty low," Musk was determined to survive on $1 a day by buying food at the supermarket in bulk.
"I went more for the hotdogs and oranges, you do get really tired of hot dogs and oranges after a while," said Musk. mixing things up every now and then with some "pasta and green pepper and a big thing of sauce" which he said could "go pretty far too."
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