Four out of 10 people worldwide don't have a safe way to poop. Find out why we need a toilet revolution. We need new ideas to help reduce disease and find new ways to turn crap into valuable stuff, like fuel, fertilizer, and fresh water.

The best designs will get awards from the Gates Foundation.

Check out the interactive Infographic at Gates Foundation.

Click on the live links on the Infographic there to learn more!

It may be a laughing matter for some ... but 4 out of 10 translates to 28,13,07,988 - given that the world population currently stands at 7,032,699,723.