So next time you’re at the toilet, remember: one button press can actually help the planet. In 1596, Sir John Harington (godson of Queen Elizabeth I) invented an early version of the flush toilet.

The buttons on your toilet flush—why are there two buttons, a big one and a small one? Are you pressing the correct button, or just whichever feels right in the moment? Here’s the answer.

The buttons on your toilet flush why are there two buttons, a big one and a small one? Are you pressing the correct button, or just whichever feels right in the moment? Here's the answer.