**The SI base unit for distance is the meter, according to the International System of Units.** From this base unit, using a system of equations, a number of derived quantities are obtained, such as area, volume, speed and acceleration.

In 1791, the French Academy of Sciences first attempted the precise measurement of a meter by equating it to one 10-millionth of the Earth's meridian from a pole to the equator. Through the centuries, there were various attempts to make this measurement more precise. In 1983, the General Conference on Weights and Measures (CGPM) established the present definition. Currently, a meter is the length of the path traveled by light in a vacuum during a time interval of 1/299,792,458 of a second.