The meter (symbol: m) is the SI basic unit for distance (or length in the speech of the physical sciences). It is defined as the length of the path that light travels in an absolute vacuum for exactly 1 / (299,792,458) seconds. This definition does not change the size of the unit (see history below), but was introduced to follow the recent development of measurement techniques, where length and time can be reproduced with very high accuracy - in the case of time, up to 1013.
The meter was originally defined in 1793 as one tenth of a millionth of the distance between the equator and the North Pole. In 1799, it was redefined in terms of the prototype of the meter standard (the actual standard was changed in 1889). In 1960, the meter was redefined in terms of a number of wavelengths of selected krypton-86 emission lines. In 1983, the current definition was adopted.
One meter equals approximately 39.37 inches (3.28 feet). Imperial inch is defined as 0.0254 meters (2.54 cm or 25.4 millimeters). One meter is about 3 3⁄8 inches longer than a yard, i.e. about 39 3⁄8 inches.
1 meter is equivalent to:
exactly 1 / 0.9144 yards (approximately 1.0936 yards)
exactly 1 / 0.3048 feet (approximately 3.2808 feet)
exactly 10000/254 inches (approximately 39.3700788 inches)
The word itself comes from the Greek metron (μετρον [metron]), which means "measure", through the French mètre. The first recorded use in English is from 1797.
In the 18th century, there were two favored approaches to the definition of the standard unit of length. Some have suggested defining a meter as a pendulum length with a half-period of one second. Others proposed defining the meter as one tenth of a millionth of the length of the earth's meridian per quadrant (one quarter of the earth's circumference). In 1791, the French Academy of Sciences chose the meridian definition, using the Paris meridian, instead of the pendulum definition because of the small variation in the force of gravity over the earth's surface, which affects the pendulum period.
In August 1793, the Republican government in France decided that the standard unit of length would be 10-7 earth quadrants passing through Paris and that the unit would be called a meter. Five years later, the measurement was completed and three platinum standards and several iron copies were made. Further analyzes showed that the length of the earth's quadrant