While Bill Gates may best be known as the co-founder of $Microsoft (MSFT.US)$Microsoft Corporation (NASDAQ:MSFT), he has been gaining prominence through the years for his philanthropy, opening the doors to the Bill & Melinda Gates Foundation in 2000. Since then, the foundation has doled out more than $79 billion to fund healthcare and education initiatives, among others.

The tech billionaire took to Twitter Inc (NYSE:TWTR) in July to announce an additional $20 billion donation to the foundation, while essentially saying he doesn't want to be rich anymore and would rather return his resources to those who need them most.

"As I look to the future, I plan to give virtually all of my wealth to the foundation. I will move down and eventually off of the list of the world's richest people," Gates wrote on the platform.

Gates is currently the world's fifth-richest person, according to Bloomberg's Billionaire Index — the $20 billion donation could send him to the eighth spot on the list, moving close friend and fellow billionaire Warren Buffett to the seventh spot.

He also took the time to thank Buffett for donating nearly half of the resources the foundation controls.

"Although the foundation bears our names, basically half our resources have come from Warren Buffett," Gates wrote, "his incredible generosity is a huge reason why the foundation has been able to be so ambitious. I can never adequately express how much I appreciate his friendship and guidance."

The foundation intends to increase its yearly spending to $9 billion by 2026, up from the $6 billion being spent per year right now.

With the support and guidance of our board, we plan to increase our spending from nearly $6 billion per year today to $9 billion per year by 2026. To help make this spending increase possible, I am transferring $20 billion to the foundation's endowment this month. pic.twitter.com/ybLMAKPx7I

— Bill Gates (@BillGates) July 13, 2022

"I have an obligation to return my resources to society in ways that have the greatest impact for reducing suffering and improving lives," the billionaire concluded, "and I hope others in positions of great wealth and privilege will step up in this moment too."

Separate from the Bill & Melinda Gates Foundation, Buffett, Gates and Melinda French Gates founded The Giving Pledge in 2010 as a "movement of philanthropists who commit to giving the majority of their wealth to philanthropy or charitable causes, either during their lifetimes or in their wills."

The pledge has more than 231 signatories in 28 countries.