A lawn mower is a machine that cuts grass to keep it short and even. Most lawn mowers have a spinning blade underneath that slices through grass blades as you push or drive the machine across your yard.

There are several types. Push mowers require you to walk behind and provide the power yourself. Riding mowers are like small tractors you sit on and drive, useful for large yards. Some modern robotic mowers operate automatically, like a Roomba for your lawn.

Before lawn mowers were invented in the 1830s, people kept grass short by letting sheep or other animals graze on it, or by cutting it with scythes (long-handled blades you swing back and forth). The invention of the lawn mower made maintaining yards much easier and helped create the tidy suburban lawns common today.

Many kids earn money by mowing neighbors' lawns in summer. Operating a lawn mower requires focus and care: you need to watch for rocks, sticks, or toys that could damage the blade or be thrown as dangerous projectiles. The job teaches responsibility and the satisfaction of transforming an overgrown, shaggy yard into something neat and well-kept.