Imagine being a billionaire at 21. Entrepreneur, social media star and model Kylie Jenner has become the world's youngest self-made billionaire. She became a billionaire two years earlier than Mark Zuckerberg. Jenner made most of her money from her cosmetics business. She started this at the age of 15 and owns the company. It generates an estimated $360 million in annual sales. It is estimated to be worth around $900 million.

Kylie Kristen Jenner was born in 1997. She got into business when she was 14 and created clothing for a fashion brand. A year later, she launched her own cosmetics line. 'Time' magazine called her one of the world's most influential teens. Today, she is a successful model, TV reality star and social media personality and influences the fashion industry. Talking about being a billionaire, she said: "That's a nice pat on the back.…I work really hard."