Life is anything but ordinary when your mom and dad are some of the richest people in the world.

Sure, Bill and Melinda Gates children may go to school, play sports, and have Instagram accounts like any other American teenager, but when their dad is worth nearly $90 billion, there's no escaping the privilege of wealth.

Keep scrolling to meet the Gates children and more kids of the richest billionaires in tech.

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Bill and Melinda Gates have three children: Jennifer, Rory, and Phoebe. The Gates have famously decided to dedicate most of their $89 billion fortune to charity and forgo setting up massive trust funds for their children, a decision Bill says the kids are "proud of."

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Source: Business Insider, Forbes 

The Gates' eldest child, Jennifer, is a senior at Stanford University and rides on the US Equestrian team. Despite her dad's status as one of the most famous tech moguls in the world, Jennifer grew up with limited access to technology around the house.

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Source: Instagram, Business Insider 

The 21-year-old appears to be dating Egyptian equestrian rider Nayel Nassar. He previously studied economics and management at Stanford.

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• Bill Gates is an alum of Lakeside School, a private school in the Seattle, Washington, area where he met Microsoft cofounder Paul Allen.
• Two of Gates' kids have graduated from Lakeside School and his youngest child is currently enrolled there.
• The annual cost to attend Lakeside School is $33,280 a student for the 2017-2018 school year.

Bill Gates may not be leaving much of his $89 billion fortune to his three kids, but he is setting them up to follow in his footsteps.

Gates was born and raised in Seattle, Washington, and enrolled at Lakeside School, a private day school located on the shores of Lake Washington, when he was 13. While there, Gates discovered a love of computers and met Paul Allen, with whom he later cofounded Microsoft.

Gates' two eldest children, 21-year-old Jennifer and 18-year-old Rory, have both graduated from Lakeside and 16-year-old Phoebe is currently enrolled there. Jennifer is now a student at Stanford University.

"Lakeside was one of the best things that ever happened to me," Gates said in a speech he gave at the school in 2005. He was announcing a $40 million donation to Lakeside to help build its financial aid fund.

"The experience and insight Paul Allen and I gained here gave us 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," he said. "If there had been no Lakeside, there would have been no Microsoft."

Gates wasn't always so fond of Lakeside, however. "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," he said in his speech.

"But I decided to do as well as I could on the test, and luckily, I got in," Gates said. "Now I'm finally prepared to say what no son ever wants to say, especially in public: 'Dad, you and Mom were right.'"

The school is now co-ed and accommodates grades 5 through 12 — a total of about 860 students. The 2017-2018 annual cost to attend is $33,280, not including additional fees for textbooks, hot lunches, a laptop, and to-and-from school transportation, which can cost up to $4,700 for a first-year Upper School student.

While more than 80% of students participate in the visual and performing arts program each year at Lakeside, the school is renowned for its excellence in STEM. Niche, a company that researches and compiles information on schools, ranks Lakeside No. 1 for best STEM high schools in Washington state, and No. 10 for best STEM high schools in America.

Whether the Gates children were admitted to the school with the help of their famous father's alum status is unclear, but the general application process for students is rigorous. According to Private School Review, Lakeside's acceptance rate is just 17%.

SEE ALSO: Meet the kids of the world's richest tech billionaires

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NOW WATCH: How Bill Gates makes and spends his billions

• Zhang Zetian, the wife of the JD.com CEO, is only 24 years old and worth about $11.6 billion.
• She works with her husband, Richard Liu Qiangdong, on JD.com's luxury items as well as public welfare.
• She's met with Bill Gates, studied at Barnard College in New York, and attended Paris Haute Couture Week.
• She is now China's youngest female billionaire.

Zhang Zetian made the rounds at last month's Paris Haute Couture Week, and her appearance in the front row of Dior, Chanel and Chinese homegrown couturier Guo Pei stirred up a media frenzy.

Zhang, who married Richard Liu Qiangdong, founder and CEO of Chinese e-commerce giant JD.com in 2015, surely has a spot among the couture clients – not only because of her wealth but also for her efforts to promote JD.com’s fashion and luxury portfolios.

According to Chinese business magazine New Fortune, Zhang made the magazine’s yearly ranking of the top 500 richest people in China along with her husband, making her one of China’s youngest female billionaires at the age of 24. Liu, whose net worth is around US$11.6 billion, also ranks number 16 on Forbes’ China Rich List.

Zhang has been actively promoting JD.com’s luxury portfolio as well as the e-commerce giant’s public welfare projects. She has also invested in a variety of companies such as Uber as part of Liu’s family fund portfolio.

In March, she met with Bill Gates at the launch of JD's public goods fundraising platform. In April this year, Zhang represented JD at the American Apparel and Footwear Association Gala. More recently, she attended red carpet events during the Cannes International Film Festival.

The natural beauty grew up in the limelight. She first rose to fame in 2009 on the internet when a photo of her holding a cup of milk tea went viral – hence her nickname as "sister milk tea."

She also refused an offer by famous filmmaker Zhang Yimou to star in one of his films.

A veteran aerobic gymnast, Zhang was admitted to top Chinese university – Tsinghua University – in 2011. She met Liu while she was studying at Barnard College in New York as an exchange student.

After dating for about three years, the couple tied the knot in Beijing in August, 2015 and held a lavish ceremony in Sydney two months later. Zhang gave birth to the couple’s first baby girl in March 2016.

SEE ALSO: The incredible career of Jeff Bezos' wife MacKenzie, an acclaimed writer who quit her job to support her husband and is now half of the richest couple in the world

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NOW WATCH: How couples improved their sex lives in just one week

Rich people love spending money on real estate, whether it's a loft in London or a mansion in Beverly Hills — or both.

Wealth-X, a firm that does research on ultra high net worth (UHNW) people, shared data with Business Insider on the residential addresses of people with a net worth of $30 million or more.

The firm found that 14,574 UHNW people own property — whether a primary home or a vacation spot — in New York, the most of any city in the world.

Below are the 17 cities where the world's richest people either live or own a vacation home.

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17. Munich

Total UHNW population: 1,352

UHNW residents: 1,060

UHNW second homeowners: 292

16. Milan

Total UHNW population: 1,731

UHNW residents: 800

UHNW second homeowners: 931

15. Toronto

Total UHNW population: 2,021

UHNW residents: 1,760

UHNW second homeowners: 261

With a net worth of $88.3 billion, Microsoft cofounder Bill Gates is the richest man in America.

It shouldn't be too surprising that one of the wealthiest people in the world also has an insanely extravagant home.

It took Gates seven years and $63 million to build his Medina, Washington, estate, named "Xanadu 2.0" after the fictional home of Charles Foster Kane, the title character of "Citizen Kane."

At 66,000 square feet, the home is absolutely massive, and it's loaded to the brim with high-tech details.

We've rounded up some of Xanadu 2.0's most over-the-top features here.

SEE ALSO: WHERE ARE THEY NOW? What happened to the people in Microsoft's iconic 1978 company photo

It's worth at least $124 million today.

According to the King County public assessor's office, the property is worth $124.99 million as of this year. Gates purchased the lot for $2 million in 1988.

Per public filings, he paid $1,041,292.55 in property taxes in 2017.

Half a million board-feet of lumber was needed to complete the project.

The house was built with 500-year-old Douglas fir trees, and 300 construction workers labored on the home — 100 of whom were electricians.

A high-tech sensor system helps guests monitor a room's climate and lighting.

When guests arrive, they're given a pin that interacts with sensors located all over the house. Guests enter their temperature and lighting preferences so that the settings change as they move throughout the home. Speakers hidden behind wallpaper allow music to follow you from room to room.

• John Collison, the cofounder and president of Stripe, is the world's youngest self-made billionaire at 27.
• He started Stripe, designed to transform the way people make online payments, with his older brother when he was just 19.
• Originally from a small town in Ireland, he came to the US to attend Harvard — until he dropped out to focus on Stripe in Silicon Valley.

John Collison founded the tech company Stripe in 2010, when he was only 19.

Now Collison, 27, can call himself the youngest self-made billionaire in the world, with a net worth totaling $1.1 billion after Stripe's $9 billion valuation in 2016. The company was designed to transform the way websites accept online payments, and it's a favorite of huge companies like Lyft and Facebook.

Collison started the company with his older brother Patrick, Stripe's CEO. Though the siblings have struck Silicon Valley gold, they haven't forgotten their humble roots in small-town Ireland.

Today, Collison enjoys flying planes, running, and hiking with members of the Stripe team.

Read on to learn more about the world's youngest self-made billionaire.

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John was born in Limerick, Ireland, in 1990, and his family eventually settled in the small village of Dromineer.

Source: Bloomberg

Collison, a brilliant student, finished with the highest possible marks on his Leaving Certificate, the equivalent of final exams in the US.

Source: Independent

Collison was accepted into Harvard before even taking his final exams, which he aced anyway.

Source: Independent

• The Winklevoss twins have amassed a Bitcoin fortune worth about $1.3 billion as of Tuesday.
• Bitcoin's price has exploded over the last two years, leading some experts to call it a bubble.

The Winklevoss twins made a big bet on Bitcoin— and it looks like it's paid off.

Cameron and Tyler Winklevoss have amassed a Bitcoin fortune worth about $1.3 billion as of Tuesday, according to estimates from the New York Times.

The twins bought about 120,000 Bitcoins back in when the price was less than $10 per bitcoin. They bought the cryptocurrency with the $65 million settlement they got in their lawsuit against Mark Zuckerberg over claims that they came up with the idea for Facebook.

Fast-forward several years: the price of Bitcoin has skyrocketed, and so has the value of their investment. And they have also racked up "an additional $350 million or so" of other virtual currencies, most of it in Ethereum.

The twins said they might think about selling when the value of all Bitcoin in circulation is on par with all the gold in the world — about $7-8 trillion compared to the $310 billion value of all Bitcoin on Tuesday. But Tyler Winklevoss added that even that might not be the tipping point since "Bitcoin is more than gold."

Bitcoin's price has exploded over the last two years. Its rapid ascent, and the cottage industry that has started to grow around it, have both galvanized investors' interests and elicited their fair share of criticism.

Earlier this year, JPMorgan CEO Jamie Dimon called it "a fraud" that is "worse than the tulip bulbs," referring to the 17th century Dutch tulip-mania bubble.

People outside the finance world have started to take notice as the price of Bitcoin keeps soaring higher. Some have even started to do creative things to get in on the action, like taking out mortgages to buy Bitcoin or purchasing the cryptocurrency with credit cards.

But, as the NYT put it, the Winklevoss' experience might be a good, cautionary reminder for regular investors that "the biggest winners have been a relatively small number of early holders who had plenty of money to start with and have been riding a price roller coaster for years."

Check out the full report at The New York Times »

SEE ALSO: People are putting their homes at risk to buy Bitcoin

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NOW WATCH: PAUL KRUGMAN: Bitcoin is a more obvious bubble than housing was

In a slice of San Francisco known as the Gold Coast, a residential enclave that has long housed the city's old-money families, blue bloods and tech oligarchs now live as neighbors.

Members of the high-tech elite, including Oracle's Larry Ellison, Apple's Jony Ives, and Zynga's Mark Pincus, have left Silicon Valley for the tony mansions, sweeping views, and exclusivity of the Pacific Heights neighborhood. The area boasts a median home sale price of $2.09 million.

We spent an afternoon in Pacific Heights to see why it attracts the technorati, and how it's changed over time.

Robert Johnson and Madeline Stone contributed reporting to this article.

SEE ALSO: Inside the most expensive zip code in America, where tech moguls like Eric Schmidt and Paul Allen have their mansions

I started my journey with a hearty breakfast at an unpretentious-looking restaurant called Sweet Maple in Lower Pacific Heights. The menu cannot claim the same modesty.

The restaurant is known for its "millionaire's bacon," a thick-cut, sweet-and-spicy version of the breakfast staple that costs $4 a slice. Its decadence at least made me feel rich.

Learn more about the breakfast craze sweeping San Francisco »

After breakfast, I headed north on Fillmore Street into the den of luxury.

• The 500 wealthiest people in the world got $1 trillion richer in 2017 according to a new Bloomberg report.
• The Bloomberg Billionaires Index revealed that total fortunes hit more han $5 trillion.
• 67 new and hidden billionaires were also discovered in 2017.

The 500 wealthiest people on the planet got $1 trillion richer in 2017, according to a new report from Bloomberg.

The staggering 23% increase is more than four times higher than last year, and brought total fortunes to more than $5 trillion.

The Bloomberg Billionaires Index, a daily ranking of the 500 richest people in the world, revealed that billionaires controlled $5.3 trillion by the end of trading on December 26, up from $4.4 trillion on December 27, 2016.

The 440 billionaires on the Index who added to their fortunes in 2017 gained a combined $1.05 trillion.

Amazon founder Jeff Bezos regained the title of richest person in the world in October, knocking Microsoft co-founder Bill Gates to second and adding the most wealth in the world throughout the year with a $34.2 billion gain.

Bezos' net worth topped $100 billion at the end of November and currently sits at $99.6 billion.

Gates, meanwhile, has a net worth of $91.3 billion, having donated much of his fortune to charity this year, including a $4.6 billion donation to the Bill & Melinda Gates Foundation in August. 

He wasn't the only one who dropped on the list due to donating a substantial amount of cash — George Soros revealed in October that his family office had given $18 billion to his Open Society Foundations over the past several years, according to Bloomberg, putting Soros at number 195 on the Index with a net worth of $8 billion.

A big year for tech

The 38 Chinese billionaires on the Index added $177 billion in 2017, a 65% gain that was the biggest of the 49 countries represented, according to Bloomberg. The number of Asian billionaires also surpassed the U.S. for the first time, according to a UBS Group AG and PricewaterhouseCoopers report.  

Still, the U.S. has the largest presence on the Index, with 159 billionaires who added $315 billion, an 18% gain that gives them a collective net worth of $2 trillion.

Meanwhile, the 57 technology billionaires on the Index added $262 billion, a 35% increase that was the most of any sector on the list.

Facebook co-founder Mark Zuckerberg had the fourth largest U.S. dollar increase on the Index, adding $22.6 billion, or 45%.

The Index also discovered 67 hidden billionaires in 2017, including Renaissance Technologies' Henry Laufer, fish billionaires Vitaly Orlov of Russia and Chuck Bundrant of Trident Seafood, New York real estate moguls Ben Ashkenazy and Joel Wiener, and bitcoin investors Tyler and Cameron Winkelvoss.

A billion 'doesn't buy what it used to'

However, 60 of the top 500 did not add to their fortunes, and 58 some even saw them fall, losing a combined $46 billion.

French telecommunications billionaire Patrick Drahi saw his fortune drop 39% to $6.3 billion, while Prince Alwaleed Bin Talal — the richest person in Saudi Arabia — dropped $1.9 billion to $17.8 billion after a crackdown against corruption.

Sixty billionaires also fell from the ranking completely.

According to Bloomberg, as the wealth of the richest people in the world skyrockets, a billion dollars "doesn't buy what it used to," with house prices hitting $300 million, the cost of divorce at $1 billion, and a painting by Leonardo da Vinci selling for $450.3 million at a Christie’s auction in November, the most expensive work ever sold.

"It’s part of the second-most robust and second-longest bull market in history," Mike Ryan, chief investment officer for the Americas at UBS Wealth Management, told Bloomberg. "Of all the guidance we gave people over the course of this year, the most important advice was staying invested."

Join the conversation about this story »

NOW WATCH: We talked to Nobel Prize-winning economist Paul Krugman about tax reform, Trump, and bitcoin

Just after Christmas, Alexa Dell got engaged to Harrison Refoua.

Dell, 24, is a daughter of Dell Technologies CEO Michael Dell, who, with a net worth of nearly $24 billion, is one of the wealthiest people in the world. Her fiancé, Refoua, is a millionaire real-estate investor. He presented Dell with a 12-carat diamond that could be worth up to $3 million.

Read on to learn more about Alexa Dell's glamorous life.

SEE ALSO: The fabulous life of billionaire Michael Dell, who just completed a $67 billion mega-deal to cement his empire

This is Alexa Dell, 24 years old.

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Dell's parents are Michael (pictured below) and Susan. Michael is the CEO of Dell Technologies and is worth nearly $24 billion, according to Forbes.

Source: Forbes

The Dells have four children together: Zachary, Juliette, Alexa, and Kira.

Source: Forbes

On Tuesday, Amazon CEO Jeff Bezos reached a $105 billion net worth, making him the richest person in the world — and ever in history.

A recent study released by Oxfam found since 2015, the top 1% has owned more wealth than the rest of the world's population — and if these top billionaires continue to see returns on their wealth, we could see the world's first trillionaire in as little as 25 years.

Ahead, nine of the world's wealthiest people — according to Forbes' Billionaire List — that own almost as much as half the world's population. All net worth estimates are current as of the time of publication.

SEE ALSO: 7 mind-blowing facts about Amazon CEO Jeff Bezos' $105 billion fortune

9. Michael Bloomberg — $51.4 billion

In 1981, Michael Bloomberg founded the financial information and media company Bloomberg LP. With an 88% stake in the business, he profits from its revenue of $9 billion.

8. Larry Ellison — $59.7 billion

In 1977, Larry Ellison co-founded the software company Oracle, which originally was launched with $2,000 of funding, $1,200 of which came out of Ellison's own pocket. Ellison stepped down as CEO in 2014, but continues to be involved with the company.

7. Bernard Arnault — $64.8 billion

Bernard Arnault has been the CEO of LVMH, which houses brands such as Louis Vuitton, Sephora, and Dom Perignon, since 1989. Combined, the brands under LVMH sold $40 billion in sales in 2016.    

• Some of the world's richest people are famously frugal.
• Warren Buffett lives in a modest home he bought in 1958 and eats McDonald's for breakfast every morning.
• Jeff Bezos, the world's richest person, drove a Honda Accord until 2013. 

Frugality is a subjective term. To the average Joe it could mean eating meals at home or scouring the internet for cheap flights.

But to a billionaire it means showing up to work in a T-shirt and jeans, driving a Toyota or Volkswagen, and, in some instances, foregoing the purchase of a private jet or lavish vacation home.

Surprisingly, some of the richest people on earth are incredibly frugal, each one with their own penny-pinching habits.

From eating lunch in the office cafeteria with their employees to residing in homes worth a fraction of what they could afford, these nine self-made billionaires — many of whom are also generous philanthropists— know the secret to keeping their net worth high.

SEE ALSO: 7 mind-blowing facts about Amazon CEO Jeff Bezos' $105 billion fortune

DON'T MISS: 24 mind-blowing facts about Warren Buffett and his $87 billion fortune

Jeff Bezos, Amazon founder and CEO, was still driving a Honda Accord as a billionaire.

Net worth: $109 billion

Amazon founder and CEO Jeff Bezos may be the richest person on earth, but as of 2013, he was still driving a Honda Accord, according to Brad Stone's book "The Everything Store." 

From the driver's seat of his Accord, Bezos told Bob Simon during a 1999 "60 Minutes" interview that "this is a perfectly good car."

Before that, Bezos was driving a 1987 Chevy Blazer, which he used to deliver packages to the post office in the early days of Amazon.

Warren Buffett, chairman and CEO of Berkshire Hathaway, still lives in the same home he bought for $31,500 in 1958.

Net worth:$91.7 billion

The "Oracle of Omaha" is one of the wisest and most frugal billionaires around. Despite his status as one of the richest people on earth, he still lives in the same modest home he bought for $31,500 in 1958, doesn't carry a cellphone or have a computer at his desk, and once had a vanity license plate that read "THRIFTY," according to his 2009 biography. And when his friend of 25 years Bill Gates visits Omaha, Buffett picks Gates up from the airport himself.

Buffett also has a decidedly low-brow palate, known not just for investing in junk-food purveyors like Burger King, Dairy Queen, and Coca-Cola, but also for filling up on them as well. The Buffett diet includes five Cokes a day, as well as Cheetos and potato chips.

At his annual shareholder's meeting in 2014, Buffett explained that his quality of life isn't affected by the amount of money he has:

"My life couldn't be happier. In fact, it'd be worse if I had six or eight houses. So, I have everything I need to have, and I don't need any more because it doesn't make a difference after a point."

Mark Zuckerberg, founder and CEO of Facebook, drives a manual-transmission Volkswagen hatchback.

Net worth:$74.2 billion

Despite his status as one of the richest tech moguls on earth, Mark Zuckerberg leads a low-key lifestyle with his wife Priscilla Chan and their young daughter. The founder of Facebook has been unabashed about his simple T-shirt, hoodie, and jeans uniform.

"I really want to clear my life to make it so that I have to make as few decisions as possible about anything except how to best serve this community," Zuckerberg said.

The trappings of wealth have never impressed the 33-year-old, who in December 2015 announced he would donate 99% of his Facebook shares during his lifetime.

Zuckerberg chowed down on McDonald's shortly after marrying Chan in 2012 in the backyard of their $7 million Palo Alto home — a modest sum for such an expensive housing market and pocket change for a man worth more than $70 billion. In 2014, he traded in his $30,000 Acura for a manual-transmission Volkswagen hatchback.

• Jeff Bezos and Bill Gates are the two richest people in the world.
• Bezos and Gates, both founders of massive tech companies, own homes less than one mile from each other in Medina, Washington.
• At least five other tech and retail billionaires own homes in Seattle suburbs.

Jeff Bezos and Bill Gates— the world's two richest people — are neighbors.

The tech titans live less than one mile from each other in Medina, Washington, a secretive and exclusive suburb located just across Lake Washington from Seattle where the median home value is over $2.7 million.

Gates isn't the only Microsoft executive to call the Seattle area home — though his $125 million state-of-the-art tech compound may take the cake. Microsoft cofounder Paul Allen, former Microsoft CEO Steve Ballmer, and Charles Simonyi, the creator of Microsoft Word and Excel — and noted space tourist— all own multi-million dollar properties within a stone's throw of Seattle.

Jim Jannard, the founder and chairman of eyewear company Oakley, and Starbucks chairman and former CEO Howard Schultz also live in the area.

Perhaps the easy commute is part of the draw of Medina for Bezos and Gates.

About 10 years before Bezos and Amazon descended upon Seattle, Gates brought Microsoft's headquarters to Redmond, Washington, a town 20 minutes from his house.

Over the past two decades, Bezos has transformed Seattle's South Lake Union neighborhood into "Amazonia," occupying more square feet of office space than the next 40 largest employers in the city combined, reports the Seattle Times. Blue Origin, the space company owned by Bezos, is about 25 miles south of Medina.

But Bezos may soon become bi-coastal, as he hunts for a city to host Amazon's second headquarters — nicknamed HQ2. There's speculation he'll choose Washington, DC, where he owns a $23 million mansion in the high-profile Kalorama neighborhood. Plus, the Bezos-owned newspaper The Washington Post is based nearby. 

SEE ALSO: One walk through Seattle's 'Amazonia' neighborhood made me very uneasy for whatever city gets HQ2

DON'T MISS: Jeff Bezos has passed Bill Gates to become the richest person in history — here’s the secretive waterfront town where both billionaires live

Join the conversation about this story »

NOW WATCH: Why Amazon's new headquarters sweepstakes makes it the 'smartest company in the world'

• Elon Musk, CEO of Tesla and SpaceX, has a net worth around $21.5 billion.
• Musk has never received a paycheck from Tesla, refusing his $56,000 minimum salary every year.
• He now says he will not receive any form of payment or compensation until Tesla reaches $100 billion in market cap.

Elon Musk may be the world's richest rocket scientist.

The 46-year-old CEO of Tesla and SpaceX and cofounder of OpenAI has said he won't be happy until we've escaped Earth and colonized Mars. Luckily, he has the mind and the money to make it happen.

Despite a massive net worth hovering around $21.5 billion, Musk has never taken a paycheck from Tesla, refusing his $56,000 minimum salary every year.

On Tuesday, Tesla announced it would pay Musk nothing for the next 10 years — no salary, bonus, or stock — until the company reaches a $100 billion market cap. If and when that happens, Musk could potentially overtake Amazon CEO Jeff Bezos as the richest person in the world.

A notorious workaholic, Musk doesn't spend cash on lavish vacations or expensive hobbies. Instead, the entrepreneur spends most of his time at the office or in factories, retreating to one of his four Los Angeles mansions at the end of the day.

Scroll through to find out what we know about how Musk, a father of five, amassed his fortune and how he spends it.

SEE ALSO: Mark Zuckerberg and his college-sweetheart wife, Priscilla Chan, are worth $74 billion — see their houses, cars, and travels

DON'T MISS: A look at the demanding schedule of Elon Musk, who works in 5-minute slots, skips breakfast, and largely avoids emails

As a child growing up in South Africa, Musk taught himself to code. By the time he was 12, he sold the source code for his first video game for $500.

Source: MONEY

Just before his 18th birthday, Musk moved to Canada and worked a series of hard labor jobs, including shoveling grain, cutting logs, and eventually cleaning out the boiler room in a lumber mill for $18 an hour — an impressive wage in 1989.

Sources: MONEY, Esquire - Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future

Musk got a pay cut to $14 an hour when he started a summer internship alongside his brother, Kimbal, at the Bank of Nova Scotia after cold-calling — and impressing — a top executive there.

Sources: MONEY, Esquire - Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future

Swedish business magnate Ingvar Kamprad had been at the helm of IKEA, one of the world's largest furniture stores and most beloved brands, for more than 70 years when his death was announced Sunday. 

With a net worth of $48.1 billion at its height, he was one of the world's richest self-made billionaires.

If you ask Malcolm Gladwell, whose books have been read by millions of people, Kamprad succeeded thanks to an often-unpopular personality trait: disagreeableness, and not caring if people thought he was crazy. 

From humble beginnings selling holiday tchotchkes to his neighbors as a child, here's how Kamprad started a privately held $11.8 billion furniture revolution and became a billionaire.

SEE ALSO: The 25 richest self-made billionaires

SEE ALSO: Ikea's Strategy For Becoming The World's Most Successful Retailer

Kamprad was born in the south of Sweden in 1926 and by the age of 5 began selling matches for profit. At 10, he rode his bike around the neighborhood to sell Christmas decorations, fish, and pencils.

Source: Business Insider, Sweden.se

In his teens, Kamprad became involved in a Nazi youth movement by the influence of his German grandmother, who was "a great admirer of Hitler." He later described that time as "the greatest mistake of my life" and even penned a letter to his employees asking their forgiveness.

Source: Telegraph, Fortune

When Kamprad was 17, his dad gave him a cash reward for making good grades in school despite his dyslexia. He used the money to found IKEA in 1943. Kamprad didn't introduce furniture until five years in; he'd started by selling small household items, like picture frames.

Source: Business Insider

• Forbes on Wednesday released its first-ever list of the richest people in bitcoin and cryptocurrency.
• Most of the people on the list are the founders and CEOs of the biggest companies in blockchain, the technology underpinning cryptocurrencies like bitcoin.
• They're worth more than $17 billion and as much as $24 billion, though that number fluctuates daily with price swings in the crypto market.

The life of a crypto-billionaire is stressful.

After unprecedented gains over the past year — driving bitcoin, ether, and Ripple's XRP up 1,300%, 8,000%, and 32,000% — cryptocurrencies have come back down to earth in recent weeks.

As of Friday afternoon, bitcoin was down 28% since late January. On Monday, bitcoin hit $7,000, down 64% from its all-time high of nearly $20,000 in late December.

And as of Tuesday, the total value of all digital currencies had dropped by 61% from its peak on January 7, to $320 billion from $826 billion.

While stories abound of regular people making fortunes in crypto, the world's richest in the space are primarily those making the pans and shovels in the digital gold rush.

On Wednesday, Forbes magazine released its first-ever list of the richest people in cryptocurrency, similar to its Forbes 400 annual list, which dates back to 1982. The values are estimates based on the price of cryptocurrencies as of January 19.

In his letter explaining why the magazine created the list, Forbes' editor, Randall Lane, said such transparency could help the crypto industry move out of its shadowy beginnings to financial maturity.

Meet the world's richest bitcoin billionaires:

SEE ALSO: A certified financial planner explains just how risky of an investment bitcoin is

13. Valery Vavilov, 38, founded the bitcoin-mining company BitFury in 2011, which has mined about 800,000 bitcoins and employs 400 people. He's worth $500 million to $700 million.

12. Dan Larimer, BlockOne's 35-year-old chief technology officer who helped found three blockchain platforms, is worth $600 million to $700 million.

11. Brendan Blumer is the 31-year-old CEO of BlockOne, the company behind the blockchain platform EOS.IO. He is worth $600 million to $700 million.

• New York City, London, and Tokyo are the richest cities in the world.
• Private wealth could be a better way to measure the strength of an economy than GDP, according to a new report.
• The world's total private wealth amounts to $215 trillion.

Citizens of the world control about $215 trillion in private wealth, according to New World Wealth's latest report.

In each of the top 10 richest cities, residents have combined wealth of at least $1 trillion, and as much as $3 trillion. Total private wealth includes all assets — property, cash, equities, and business interests — minus any liabilities.

According to New World Wealth's research, total private wealth is "a far better gauge of the financial health" of an economy than GDP. Ultimately, the wealth of a public signifies its spending power.

To be sure, these cities rank highly because of two factors: a large general population and a significant amount of high-net-worth residents. Across the world, there are about 15.2 million people with net assets of $1 million or more, while the average person has net assets of $28,400.

Below, check out the top 10 richest places in the world ranked by total private wealth of all residents.

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9 (TIE). Singapore — $1 trillion total private wealth

9 (TIE). Sydney — $1 trillion total private wealth

8. Hong Kong — $1.3 trillion total private wealth

• We put together a list of the world's richest black billionaires, using data from Forbes.
• The majority of the billionaires on the list are self-made self-starters who built business empires in finance, sports, media, and commodities.
• Only three of the billionaires are from the United States.

Bill Gates, Warren Buffett, and Jeff Bezos may be the richest men in the world, but they aren't the only billionaires.

There are 2,043 people across the globe with three commas in their net worths, according to the 2017 Forbes Billionaires list. The 23 wealthiest have $1 trillion collectively.

In 2017, 10 of the world's billionaires — fewer than 1% — are black, down from 12 last year, reports Forbes contributor Mfonobong Nsehe. Three of the 10 are women. All but one, Isabel Dos Santos, are billed by Forbes as self-made.

To compile the full list, Forbes uses stock prices and exchange rates to estimate the net worths of the world's richest people, and then ranks them based on their wealth. We updated the 2017 list using data from February 15, 2018. Forbes maintains a current snapshot of the world's billionaires, updated daily.

Continue reading to see the richest 10 black billionaires in the world, according to our updated version of the 2017 Forbes Billionaires list.

SEE ALSO: Meet the richest man in Africa — the only black billionaire among the world's 50 richest people

DON'T MISS: Meet the world's 50 richest billionaires of 2018

10. Mohammed Ibrahim, $1.18 billion

Self-made billionaire, 71 year-old Mohammed Ibrahim, was born in Sudan and now lives in the United Kingdom, where he is the 11th wealthiest citizen. Ibrahim became a billionaire after selling his telecommunications company, Celtel International, in 2005, according to Forbes.

Now he spends much of his time focusing on improving the lives of African citizens through the Mo Ibrahim Foundation.

Net worth: $1.18 billion

Age: 71

Citizenship: Sudan

Industry: Telecommunications

Source of wealth: Self-made

9. Folorunsho Alakija, $1.49 billion

Folorunso Alakija, vice chair of Nigerian oil company Famfa Oil, got her start in business as the founder of an elite Nigerian fashion label, according to Forbes.

The 66 year-old self-made billionaire lives in Lagos, Nigeria and has four children. Her son, Folarin Alakija, recently married Iranian model Nazanin Jafarian Ghaissarifar, in a lavish, multi-million dollar wedding, which took place in England.

Net worth: $1.49 billion

Age: 66

Citizenship: Nigeria

Industry: Oil, Retail

Source of wealth: Self-made

8. Michael Jordan, $1.65 billion

One of the most successful athletes of all time, Michael Jordan, 54, made a total of $90 million as a basketball player, according to Forbes. Since retiring from the NBA, he has amassed the majority of his wealth through his relationship with Nike and other corporate partnerships.

Jordan, who also owns a stake in the Charlotte Hornets, now makes more in one year than he did during his entire professional basketball career, as Business Insider's Cork Gaines reported.

Net worth: $1.65 billion

Age: 54

Citizenship: United States of America

Industry: Basketball, Retail

Source of wealth: Self-made

China is home to more than 10% of the world's billionaires — and a whopping 94% of them are self-made, according to a new report from Wealth-X.

Over the last several years, China's billionaire population has grown rapidly thanks to robust developments in tech, retail, and real estate. The average Chinese billionaire has a net worth of $2.7 billion.

But since so many Chinese billionaires are relatively new to the 10-figure club, according to Wealth-X, "most are still in the wealth-creation rather than the wealth-preservation stage," and have far less liquid cash than their American and European counterparts.

Below, meet the 10 richest Chinese billionaires, whose fortunes range from $14 billion to over $41 billion.

SEE ALSO: Meet the world's 10 richest black billionaires

DON'T MISS: 9 mind-blowing facts about the world's richest people

Jiehe Yan

Net worth: $14.1 billion

Company: Founder, China Pacific Construction Group

Industry: Construction

Zhidong Zhang

Net worth: $15 billion

Company: Advisor, Tencent Holdings 

Industry: Media/Entertainment 

Jun Lei

Net worth: $15.1 billion

Company: Chairman, Xiaomi 

Industry: Electronics

• The Waltons are the richest family in America. 
• They have a combined wealth of $133 billion, according to Bloomberg.
• In public, they live a pretty modest life. This is how they spend their fortune.

The Waltons are the richest family in America, but they're pretty discreet about it. 

According to Bloomberg's Billionaires Index, the Walmart heirs have a combined wealth of $133 billion, which is more than Jeff Bezos, Bill Gates and Warren Buffett. In fact, they are worth about $33 billion more than the second richest family in the US, the Kochs. 

Despite their fortune, the Waltons seem to live a pretty modest life, at least in public. 

Here's what we do know about how the wealthy family spends its fortune: 

SEE ALSO: Walmart's Alice Walton is the richest woman in the world — here's how she spends her $43.7 billion fortune

Sam Walton, who died in 1992, opened the first Walmart store in Arkansas in 1962.

He was married to Helen Ronson. Together, they had four children: Rob, John, Jim, and Alice.

The Walton family own 50% of Walmart's total stock between them. 

This is Samuel Robson "Rob" Walton, the oldest Walton son. He served as chairman of Walmart until 2015.