A wedge is a simple tool with a thick end that tapers down to a thin, sharp edge. When you push a wedge into something, the slanted sides force things apart. An axe blade is a wedge: when you swing it into a log, the wedge shape splits the wood. A doorstop is a wedge that slides under a door to hold it open. Even your front teeth are wedges, designed to bite through food.

Wedges are one of humanity's oldest inventions, used for thousands of years to split rocks, harvest timber, and build everything from pyramids to log cabins. The wedge is so fundamental that scientists classify it as one of the six simple machines that make work easier.

The word also describes a wedge-shaped piece of something, like a wedge of cheese cut from a wheel, or a wedge of pie. In golf, a wedge is a club designed to hit the ball high and short.

You can also wedge something into a tight space, like wedging your backpack under a desk, or finding yourself wedged between two tall adults on a crowded bus. When something is wedged in, it's stuck tight and hard to remove.