A speeder is someone who drives faster than the speed limit allows. When a police officer pulls over a speeder on the highway, it's usually because they were going 75 miles per hour in a 55 zone, or racing through a school zone where kids might be crossing the street.

Speed limits exist because faster speeds make accidents more likely and more dangerous. A car moving at 30 miles per hour can stop much more quickly than one going 60. Speeders put themselves and others at risk: a driver speeding through a neighborhood might not have time to brake if a ball rolls into the street with a child chasing after it.

The word can also refer to something designed to go fast. In Star Wars, Luke Skywalker rides in a landspeeder, a hovering vehicle built for speed across desert terrain. Some science fiction stories feature speeders as futuristic motorcycles or spacecraft.

Police often use radar guns to catch speeders, measuring exactly how fast vehicles are moving. Getting caught speeding usually means receiving a ticket and paying a fine.