A lawn mower is a machine used for cutting lawns or grass to a required height; they use a rotating blade or blades. Basically they can be split into two main groups, rotary mowers and cylinder mowers. The rotary mower uses a vertical axis to move around while the cylinder mower uses a horizontal axis. There are many different designs each with their own application; some are pushed manually while others are powered by electric or a combustion engine. The smaller types are usually electrically powered for the relatively small household garden while the larger ones have the capacity to be used in places like public parks and golf courses. The larger mowers can be self contained like the ride on mowers, although multi gang mowers are probably the largest, being pulled along by a tractor. The first grass mower was invented by Edwin Budding in 1827 in Thrupp, just outside Stroud in Gloucesteshire. It was originally designed to cut the lawns on sports grounds and large gardens, replacing the old scythe. Since then the designs have changed dramatically using high tech applications to achieve the perfect lawn.