People became the fastest billionaires in the shortest amount of time

Mark Zuckerberg – 4 years

The youngest, fastest self-made billionaire ever, Mark Zuckerberg's hefty Facebook holdings made him a billionaire at the tender age of 23. Zuckerberg made his first appearance on the Forbes World Billionaires List in 2008, his then-net worth totaling $1.5 billion (£1.2bn). Today, the social network boss turned philanthropist is worth an astronomical $63.3 billion (£49.2bn).