The metric system is a group of various units of measurement. Its name comes originally from the metre. It is a decimal system, which means that each unit is ten times bigger, or smaller, than the next unit. Previously, measurements were difficult to calculate; in measurements of length, for example, there were 12 inches in one foot and three feet in one yard, while weight was calculated using ounces and pounds (16 ounces in one pound).
The metric system was devised in the 1790s in France, and is now used in most countries in the world for all scientific and technical measurements.
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