The
degree Celsius is the unit of temperature on the
Celsius scale, one of two temperature scales used in the International System of Units (SI), the other being the Kelvin scale. The degree Celsius can refer to a specific temperature on the Celsius scale or a unit to indicate a difference or range between two temperatures. It is named after the Swedish astronomer Anders Celsius (1701â1744), who developed a variant of it in 1742. The unit was called
centigrade in several languages for many years. In 1948, the International Committee for Weights and Measures renamed it to honor Celsius and also to remove confusion with the term for one hundredth of a gradian in some languages. Most countries use this scale; the other major scale, Fahrenheit, is still used in the United States, some island territories, and Liberia. The Kelvin scale is of use in the sciences, with 0 K (â273.15 °C) representing absolute zero.