The International System of Units, officially known as *SystĂ¨me International* and abbreviated SI, was adopted by the eleventh General Conference on Weights and Measures in Paris in 1960. Basic units are based on the meter-kilogram-second (MKS) system, which is commonly known as the metric system.

Most of the world uses the metric system for measuring quantities such as weight. Also known as the meter-kilogram-second (MKS) system, the metric system was last refined at the eleventh General Conference on Weights and Measures in 1995.