In addition to the general guidelines for mower safety, follow these guidelines for riding lawn mowers: Before starting the engine, make sure the transmission is out of gear and the mower blade clutch is disengaged. Never allow extra riders on the lawn mower. Slow down when turning and when working on slopes. Mow up and down slopes rather than across them. Always look behind you before backing.
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A lawn mower (often spelled as one word - lawnmower) is a machine (electric or mechnical) used to cut grass to an even length. It was invented in Britain in 1830 by Edwin Beard Budding, primarily to cut the lawn on sports pitches and expansive gardens. Since many sports had just been invented in Britain that required a flat soft ground (such as croquet, tennis, football and rugby), a more efficient way of making grass a uniform length was needed, and so the lawn mower was born. Previously, grass was cut by hand using a scythe.

There are two main types of lawnmowers, those where a set of cylindrical blades spin in a vertical forwards motion, and those whose blades spin horizontally. The latter type are usually powered by engines running on gas, although versions with electric motors are becoming increasingly popular. Cordless electric lawnmowers are also available for small lawns.

The simplest kind of mower is the manual push mower. These always use the cylindrical type blades. This works by spinning the cutting blade at a fast speed, with power supplied by the user pushing it, rotating its wheels, which are then geared to the cutting blades. The blade rotates forward over the grass, pulling it into the blade and against a fixed plate - the blade and plate cause a scissor-like slicing action which cuts the grass.