Source: Bill Gates via

The richest men in the world didn't inherit their wealth; they amassed it over long entrepreneurial careers that included embracing disruptive new technologies like computers and mobile phones and stepping in to buy top-shelf businesses when others were selling.

Here's how the three richest men in the world became billionaires and what their path to success can teach everyone.

1. Bill Gates, $79.2 billion
According to Forbes, Gates' $79 billion nest egg makes him the richest man on the planet.

Gates is the founder of Microsoft, the world renown computer software Goliath responsible for the Windows operating system and the Office suite of software productivity tools.

In 1975, Gates founded Microsoft with billionaire Paul Allen, a prep school chum, to offer software for the emerging PC market. Over the next 40 years, Microsoft sales of software for personal computers turned Gates into the planet's richest man.

While his success may seem pre-ordained in hindsight, Gates' embrace of the PC didn't come without risk. At the time Gates was diving headfirst into personal computers, many doubted if the PC would make a lasting impact. For instance, the founder of business server pioneer Digital Equipment Corporation shelved plans for personal computers in the '70s, saying "there is no reason for any individual to have a computer in his home." 

Obviously, Gates willingness to look past naysayers and bet on the transformative nature of personal computing has paid off in riches, and that could be a money making lesson everyone should pay attention to.

Source: Carlos Slim Helu

2. Carlos Slim, $77.1 billion
Slim controls a conglomerate of Mexican businesses, including Latin America's largest mobile phone company, America Movil, which boasts 289 million mobile subscribers.

Although a civil engineer by training, Slim became a stock trader in Mexico during the early '60s and then in 1965, Slim founded his own Mexican brokerage firm and acquired a bottling company. The following year, he established Grupo Carso, which became the holding company for various businesses, many of which were acquired at recessionary bargain-bin prices during the 1980s peso crisis.

Today, Slim is Mexico's dominant business leader. His 220 businesses represent 40% of Mexico's stock exchange listings and his net worth is the equivalent of roughly 7% of Mexico's GDP.

Given that America Movil accounts for more than half of Slim's net worth, he owes a big chunk of his wealth to his willingness to embrace new technology and to buy when everyone else is selling. Looking beyond the moment to take advantage of weakness isn't easily done, but Slim has shown that approaching investments this way can be incredibly successful.

Source: The Motley Fool

No. 3 Warren Buffett, $72.7 billion
Buffett is famous for his treasure trove of folksy investment advice, but perhaps none of that advice sums up his investment philosophy better than this gem of wisdom offered up to investors in 2013: "It's better to have a partial interest in the Hope diamond than to own all of a rhinestone."

Buffett's passion for numbers is rivaled only by his passion for bargains, and over the past 60 years, the Oracle of Omaha has built a portfolio of top-tier companies that have made him one of the world's richest men.

Buffett's background includes stints as a paperboy, pinball machine businessman, and investment broker. But his time working for famed value investor Benjamin Graham was the most influential at shaping his investment discipline.

After leaving Graham's firm to establish an investing partnership of his own, Buffett's willingness to learn from his mistakes, including those tied to buying second-rate companies solely because they were cheap, allowed him to improve upon Graham's teachings.

Thanks to Buffett's willingness to change his approach, he's been able to build an enviable stable of first rate businesses, including the insurance giant GEICO and the iconic railroad Burlington Northern.

But Buffett also remains an active equity investor that's willing to take stakes in great companies even if he can't buy them lock-stock-and-barrel. During the last U.S. recession, Buffett orchestrated money making deals with Goldman Sachs and Bank of America that reinforce his belief that it's better to own some of something that is valuable, than all of something that is not.

Although getting in early in innovative technology and investing with an eye toward value isn't likely to make you as rich as Gates, Slim, and Buffett, mirroring their approaches might still prove to be a recipe for your long-term financial success and, for that reason, you might want to keep your eye out for the next big, disruptive trend and keep some cash on the sidelines for the next big market-buying opportunity.