The tonne, also known as the metric ton, is a unit of mass equivalent to 1,000 kilograms (kg). It is part of the International System of Units (SI) and is used worldwide, except in the United States, where customary units prevail.
The tonne was first introduced in France in the late 18th century during the metrication movement. It was standardized in 1901 to provide a clear definition based on the kilogram, which is defined by a physical prototype stored in France. The tonne became widely adopted in the 20th century as countries shifted to the metric system.
The tonne is commonly used in various fields, including trade, shipping, and scientific research. It is particularly prevalent in industries dealing with bulk materials, such as agriculture, mining, and construction. Many countries, especially those in Europe and Asia, use it as the primary unit for measuring mass.