Microsoft is not the only company Gates has founded over the years.
The father-of-three also headed up several companies including BEN, Cascade Investment, bgC3 and TerraPower.
Gates has also channelled a huge portion of his time into the Bill and Melinda Gates Foundation.
The private charity was founded by himself and Melinda in 2000.
One of the foundations breakthrough moments helped lead an early 21st centre vaccination campaign which significantly contributed towards eradicating polio in Africa.
In 2009, Gates developed The Giving Pledge alongside Warren Buffet.
The campaign encourages the extremely wealthy to contribute a majority of their wealth to philanthropic causes.
He also spends a lot of his time focussing on other philanthropic efforts including climate change, global health and development, and education.