It's probably pretty obvious that $25 billion is a lot of money. It's not a lot in terms of governments - the U.S. defense budget in 2015 alone was about $600 billion. But for an individual it’s unbelievable wealth. In fact, there are fewer than two dozen people on the planet who personally control that much money. The figure is so big that it is hard to put into ordinary terms. So how much is $25 billion?
Well, the median household income in the U.S. is about $50,000, meaning that someone with $25 billion could afford to pay to support half a million households for a year. That means someone on this list could afford to give the entire city of Atlanta the year off.
It's more than the value of the stock of United Airlines, which currently has a market capitalization of just over $20 billion. It is more than the stock value of Twitter, Wendy's, Sears, Pandora and Dreamworks Animation combined. The interest on $25 billion, even if it was only invested in treasury bonds, would be enough to buy a company the size of Angie’s List each and every year into the foreseeable future without ever touching the principal.
A fortune that size is enough that if one of the people on this list liquidated their entire investment portfolio, they could afford to buy a cheeseburger, fries and a coke from the McDonald's dollar menu for every single person on Earth (vegetarians could substitute cookies for the burger).
20 Sheldon Adelson
Whatever happens in Vegas stays in Vegas. Especially the money. Sheldon Adelson can tell you that. He's gathered a fortune worth $26.4 billion in the casino business. The 82-year-old began his career in Boston, starting small businesses as a schoolboy. He continued as a serial entrepreneur into the 1970s, but made his first real money through a company that ran trade shows, like the COMDEX computer industry show. This became his way into Vegas. He used the money earned from that venture to purchase the Sands Hotel and Casino in Las Vegas, which he eventually tore down to create The Venetian. He also has casino holdings in China, Singapore and Pennsylvania.
19 Jorge Paulo Lemann
Brazil is considered one of the next great economic success stories. While various political and economic issues have held the country back, and many parts of the nation remain in terrible poverty, Brazil's vast resources and large population make it a good candidate for strong growth in the coming decades. Right now, Jorge Paulo Lemann is the only Brazilian in the upper echelon of the world's wealthiest people. His father was from Switzerland, but Lemann was born in Rio de Janeiro. He accumulated his original fortune in Brazilian banking, and has expanded his empire through beer. Lemann built regional brewing giant AmBev, which became InBev through a merger with Belgium's Interbrew and then became Anheuser-Busch InBev after the purchase of the iconic U.S. beer maker.
18 Li Ka-shing
Li Ka-shing is seen as one of the most powerful people in Hong Kong. He has a diverse fortune, including vast holdings in shipping and in beauty products. Li represents a true up-by-his-own-bootstraps story, dropping out of school as a teenager and starting his own company in the 1950s. Through wise mergers and the help of the rise of China and Hong Kong over the past several decades, he has become one of the most recognizable billionaires in Asia. Admired for his business acumen, Li has also built a reputation as a generous philanthropist, giving away large donations to a number of causes.
17 Wang Jianlin
China has been a rising power for at least the last three decades. Vast amounts of wealth have been made, as the country has become the world's manufacturing hub, with money spreading out to all sectors of the economy. One of the biggest beneficiaries has been real estate, as China's cities have grown in both population and international prestige. This is where Wang Jianlin has made his fortune. The 61-year-old is China's largest real estate developer. He also has significant holdings in movie theaters and owns a chunk of Spain's Atlético Madrid soccer team.
16 S. Robson Walton
The largest retailer in the world is the source of a lot of wealth. Wal-Mart employs more than 2 million people around the world and generates annual revenue of more than $480 billion. It has also created three of the 20 richest people in the world, even 50 years after its founding. S. Robson Walton, known as Rob, represents the first of a Walton three-peat on the list of the world's richest people. He is the oldest son of Sam Walton, founder of Wal-Mart. In his own right, Rob is a lawyer and served a long tenure as the chairman of his father's company, taking over the position in 1992 and helping to steer the company for over 20 years. His fortune is currently valued at $31 billion. He's 72 years old.
15 Alice Walton
The only daughter among the Walton heirs, Alice Walton has made money her life's work. Besides the massive Wal-Mart fortune left to her by her father, she has made a career in finance. With a degree in economics and experience as a stock analyst, Walton started her own firm in the 1980s. She is one of only two women on this list of the 20 richest people in the world. Walton is also known for her checkered driving history. She has been arrested multiple times for driving while intoxicated and has been involved in several major car accidents. This includes a crash in 1989 that caused the death of a pedestrian.
14 Jim Walton
The last (and best performing, in terms of wealth) of the living Wal-Mart heirs, Jim Walton is the youngest son of Sam Walton. He sits on Wal-Mart's board and has a number of other family business interests, including a bank and newspaper company. The 67-year-old is currently worth $32.7 billion. He has four children. Originally, there were four children of Sam Walton. John T. Walton died in a plane crash in 2005. At the time, he was considered the 11th richest person in the world. He was survived by his wife and son, who retain his fortune.
13 Sergey Brin
The first of two founders of Google to appear on this list, Sergey Brin has ridden the search engine from a Stanford dorm room to a $35.1 billion fortune. Brin is also a true American story, complete with immigration from another country. Brin was born in what was then the Soviet Union and came to the U.S. with his family when he was a child. At Stanford, he befriended a fellow student, Larry Page, and the two eventually began working on a new method of searching for web pages. The project eventually became Google, which was founded in 1998. Along with Page, the 42-year-old Brin is among the younger members of the world's wealthiest. Only one person on the list is younger, but more on that person later in the list.
12 Bernard Arnault
French mogul Bernard Arnault has made his career transforming companies. He began with the firm his father started. In the 1970s, he used funds raised from selling the company's construction business to make investments in real estate. Through this, Arnault made his first real fortune. He then moved on to fashion, acquiring the Christian Dior brand and eventually taking control of LVMH, one of the world's largest luxury goods companies. He has also made a number of other investments over his more than 40-year business career, including providing money for Netflix. He's also a well-known art collector, with pieces by Andy Warhol and Pablo Picasso. The 66-year-old currently has a fortune valued at $35.8 billion.
11 Larry Page
While it probably isn't something they talk about very much, it must be at least a small point of pride for Larry Page that he is ever so slightly more rich (relatively speaking) than his fellow Google co-founder Sergey Brin. In the latest Forbes tally, Page is worth $35.9 billion, compared to Brin's $35.1 billion. That's only about a 2% improvement, but it also represents about $800 million. That might be close to a rounding error for the Page and Brin, but it would be enough to cause a lotto stampede if it became the next Powerball jackpot. Page is currently the CEO of Google's parent company, the recently re-named Alphabet Inc.
10 Liliane Bettencourt
Liliane Bettencourt is probably one of the least-known people to crack the top-20 wealthiest list. She's also one of only two women on the list, along with the previously mentioned Walton heir, Alice Walton. The French socialite inherited a fortune from her father, Eugène Schueller, the founder of L'Oréal. Bettencourt, who was an only child, remains a major stock holder in the cosmetics giant, giving her not only a massive fortune, but entree into the high-life world of beauty and fashion. The 93-year-old was married to politician André Bettencourt from 1950 until his death in 2007. She is worth $36.5 billion and has a single heir, her 62-year-old daughter Françoise Bettencourt Meyers.
9 Charles and David Koch
A couple of brothers are tied for the number-nine slot. Charles and David Koch are each worth $40.7 billion. Known as much for their political involvement as for their wealth, the basis of the Koch brothers' fortune is their father's oil business, which they turned into a massive conglomerate. The Koch brothers have received a good deal of attention as backers of conservative and libertarian causes. They are considered two of the most influential behind-the-scenes movers in American politics, willing to give massive amounts of money to try and swing elections. This has made them controversial figures as well, not just with people on the opposite side of the political spectrum. In a number of circles, the Koch brothers have become the face(s) of the issue regarding money in politics.
8 Michael Bloomberg
Michael Bloomberg is probably best known now as a politician. He is a former three-term mayor of New York, who had enough political juice to get the city to change its term-limit rules so that he could run for the final term. This year, he has been flirting with a presidential run, leaving open the possibility that he might run a third-party campaign if he sees a weak enough field among the major party candidates. While the last decade and a half have been dedicated largely to politics, the backbone of Bloomberg's political power is his large piles of money. Bloomberg is the founder of Bloomberg LP, a company that provides financial data services and has various media holdings, such as a self-named TV network. Thanks to these investments, Bloomberg (the person) is worth $41.3 billion.
7 Larry Ellison
Larry Ellison is the founder of Oracle Corp., a maker of business software. The company creates programs that help business in various tasks, such as manage their supply chain and organize sales efforts. The company was created in the 1970s, when Ellison was still in his early 30s. The future billionaire and two partners pooled $2,000 to form a firm that would eventually become Oracle. Now the 71-year-old is worth $45 billion and the company is the second-largest software maker in the world (behind Microsoft), with annual revenues of more than $38 billion and a profit for 2015 of almost $10 billion. Ellison is also known for his love of yachting, sponsoring a vessel in the America's Cup.
6 Mark Zuckerberg
Mark Zuckerberg, founder of the social networking giant Facebook, is by far the youngest person in this list of the 20 richest people on the planet. At 31, he's more than 35 years younger than the average age of the other people on this list. He's the only person on the list under 40 and, along with the Google guys, one of only three that are younger than 50. Zuckerberg, who famously founded Facebook as a college student at Harvard, is also the only person on the list who has had a film made about him get nominated for a Best Picture Oscar (slight-but-not-really spoiler alert: Bill Gates appears later on this list, and has been portrayed in a few movies, but none of those got the Best Picture nomination). The Social Network, which saw Zuckerberg played by Jesse Eisenberg, lost to The King's Speech.
5 Jeff Bezos
Amazon.com has been one of the biggest disruptors in American business over the past couple decades. Since its founding in the mid-1990s, the company has all but destroyed the brick-and-mortar book selling business. It has also significantly altered the rest of the retailing industry by offering a convenient and inexpensive way to order almost anything. Throughout the time that it was changing American business, the online retailer has been led by Jeff Bezos. The future mogul left a lucrative Wall Street job to found the company in 1994. Encouraged by rising Internet use, Bezos moved cross country to found the startup in Seattle. More than 20 years of expansion later, Bezos is now worth about $47 billion, good enough to crack the top five of the world's richest people.
4 Carlos Slim
Carlos Slim has slipped a little recently. For a number of years earlier in the decade, the Mexican businessman was the richest person in the world, and a symbol of the rising business potential of Latin America. While he has given up his crown and slipped to number four, he remains one of the highest-profile businessmen in the world. Slim made his fortune through a number of diverse holdings. Currently he heads telecom companies Telmex and América Móvil, but at different times during his career, he has earned money in various industries: stock trading, construction, real estate, retail and mining, just to name a few. The 76-year-old is currently worth about $53 billion.
3 Warren Buffett
Warren Buffett is America's favorite rich grandfather. The founder of investment company Berkshire Hathaway, which owns such iconic bands as GEICO and Dairy Queen, makes headlines for his down-to-earth investment advice and his liberal political leanings (he was famously upset when he found out his secretary paid a higher tax rate than he did). The so-called "Oracle of Omaha," who still lives in his native Nebraska, is worth nearly $62 billion, but has pledged to donate almost his entire fortune to charity through the Gates Foundation. And, at 85, he is one of the oldest people among the top 10 richest list. Despite being nearly 20 years past the usual retirement age, Buffett remains the CEO of Berkshire Hathaway.
2 2. Amancio Ortega
Amancio Ortega Gaona is an up-and-comer on the list of the richest people in the world. The fashion mogul from Spain founded the Inditex, one of the world's largest clothing companies. He dropped out of school in his teens and started his career as a helper in a shirt maker's shop. In the 1970s, he started building his fashion empire with a single store, called Zara. Zara is now just one of many brands in the Inditex family, which in total has more than 6500 locations worldwide. Ortega is known for his reluctance to seek the spotlight. He has avoided most media interviews and stayed away from public appearances until he needed to make the rounds as part of his company's initial public offering.
1 Bill Gates
The king stays the king. Despite all the changes in the economy over the past 20 years, Microsoft founder Bill Gates remains the richest man in the world. His name has become synonymous with "rich," making him the Rockefeller of our time. And his lead on the list of wealthiest people in the world is currently pretty solid. Depending on market fluctuations, Gates has between about $8 billion and $20 billion more than the #2 person on the list, whoever that might be. Surprisingly though, given how long he's been among the world's richest people, Gates is also among the younger people in the world's highest echelon of wealth. At 60 years old, Gates is the third youngest member of the $40 billion club (the 10 people on the planet worth more than $40 billion). He sits just behind the 52-year-old Jeff Bezos and (of course) the 31-year-old Mark Zuckerberg.