2 articles
History of the metre
The history of the meter spans from its 1790s definition as one ten-millionth of the Paris meridian quadrant to the 1983 definition fixing the speed of light.
Metre
The metre, also spelled meter (French mètre), is the SI base unit of length, defined since 1983 as the distance light travels in vacuum in 1/299,792,458 of a second.