No 1. Warren Buffett - $62.0bn

This US investor is now the world's richest man, having soared past friend and bridge partner Bill Gates. Buffett earmarked the majority of his Berkshire shares to charity in 2006, mostly to the Bill & Melinda Gates Foundation. (Saul Loeb, AFP)

No 2. Carlos Slim Helu & family - $60.0bn

Son of a Lebanese immigrant, Slim made his first fortune in 1990 when he bought a fixed line operator. He has donated close to $7bn worth of cash and stock to fund education and health projects, and to the revitalization of Mexico City's downtown historical district. (Chris Hondros, Getty)

No 3. William Gates III - $58.0bn

The famous Harvard dropout and Microsoft visionary is no longer the world's richest man. Gates is preparing to give up day-to-day involvement in the company he cofounded 33 years ago to spend more time focused on his philanthropic endeavors. (Stephane de Sakutin, AFP)

No 4. Lakshmi Mittal - $45.0bn

Mittal heads the world's largest steelmaker, $105bn ArcelorMittal, which accounts for 10% of all crude steel production. ArcelorMittal recently delivered 580 tons to be used in the construction of the World Trade Center memorial in New York. Mittal lives in London and is Europe's richest resident. (Jean-Christophe Verhagen, AFP)

No 5. Mukesh Ambani - $43.0bn

Ambani is Asia's richest resident and heads petrochemicals giant Reliance Industries. His fortune is up $22.9 billion since last year, making him the world's second biggest gainer in terms of dollars. The biggest gainer was his estranged brother Anil, who ranks 6th in the world just behind his older brother. The sons inherited their fortune from their late father, renowned industrialist Dhirubhai Ambani. (Manpreet Romana, AFP)

Mark Zuckerberg - $1.5bn

Zuckerberg is the youngest billionaire on earth and possibly the youngest self-made billionaire ever, after founding the infamously addictive social networking site, Facebook in February 2004 from his Harvard dorm room. Microsoft paid $240m last October for a 1.6% stake, giving the company an implied valuation of $15bn. (Facebook.com, AFP)

Aliko Dangote - $3.3bn

One of the only Africans named on Forbes' list of billionaire newcomers, Dangote is a success story. At age 21, Dangote borrowed some money from his uncle and became a trader. He hit the jackpot and became his nation's first billionaire, when his sugar production company listed on the Nigerian stock exchange last year. (Pus Utomi Ekpei, AFP)

Nicky Oppenheimer & family - $5.7bn

Appearing at number 173 on Forbes' billionaire list, Nicky Oppenheimer's De Beers diamond empire continues to change and grow. In 2006 Nicky sold off a third of his family's interest in global mining giant Anglo American, founded in 1917 by grandfather Ernest, to Chinese billionaire Larry Yung. (John D McHugh, AFP)

Johann Rupert & family - $3.8bn

Appearing at number 284 on Forbes' billionaire list is this affable yet reclusive head of publicly-traded Swiss luxury group Richemont. With family relatives, Rupert also owns two of South African's best-known vineyards, Rupert & Rothschild and L'omarins.(Sharief Jaffer, Rapport, Images24.co.za)

Patrice Motsepe - $2.4bn

South Africa's first black billionaire, Patrice Motsepe, was born in the sprawling black township of Soweto and then trained as a lawyer. In 1994, he bought low-producing gold mine shafts. Over time he has built an $875 million (sales) mining conglomerate, African Rainbow Minerals, with interests in precious metals. (Werner Beukes, Sapa)