'C' is the symbol of the "degree Celsius", a unit for measuring temperature that originally used a scale of 0oC for the boiling point of the water and 100oC for freezing, and was later reversed so that the difference "cold to heat" coincided with other existing scales. As the reference range is one hundred degrees it was also called "degree Celsius", but today that name is not used to not confuse it with the angular degree scale and because in reality the current thermometers use a scale with other references for grade zero. Still, it is a tribute to its creator, Swedish physicist Anders Celsius. See kelvin , K , grade Fahrenheit , F .
