If you’re a scientist, a student or a citizen of any country in the world except for the United States, Myanmar or Liberia, there’s no avoiding the metric system. The system, featuring meters, liters and kilograms, was adopted following the French Revolution and devised by a group of French scientists in an effort to create a system of standard measurements (at the time, thanks to local and regional practices, there were nearly 400 different ways to measure areas of land in France).

Ideas for a rational, decimal-based system of measurement, expressed in multiples of 10, had been around since the 17th century, however. Abandoning old royal standards, the metric system’s developers sought to express everything in terms of logic and nature. One meter was one ten-millionth of the distance between the North Pole and the Equator; a milliliter was the volume of one cubic centimeter of water, whose weight would equal one gram. The first metric system also included the “stère,” equal to the volume of one cubic meter of stacked firewood.

The metric system did not achieve immediate success. Napoleon implemented various reforms to standardize weights and measures in France and its conquered territories. The metric system continued to develop and was reinstated in 1840. By then, other countries had begun to adopt it, usually in the wake of political upheavals of their own. By the mid-20th century, meters, kilometers and milliliters were standard units (nearly) the world over.