A meter is a unit of length in the metric system, and it is equivalent to 100 centimeters or 1,000 millimeters. It is the base unit of length in the International System of Units (SI) and is widely used around the world for measuring distances. The meter was originally defined as one ten-millionth of the distance from the North Pole to the equator along a meridian passing through Paris, France. However, in 1983, the meter was redefined as the distance traveled by light in a vacuum during a specific time interval.