Calorie

A calorie is a unit of measure of the energy. One calorie is equal to the amount of energy necessary to warm one gram of water from 14.5 degree Celsius to 15.5 °C at sea level. The "Calorie" on a nutrition label is actually different from the "calorie" or unit of measure for energy. The upper case "Calorie" is actually a kilocalorie, or 1,000 calories.

The unit has been replaced by the Joule (1 cal = 4.1855 J) as standard unity of energy, it is not longer used except to express the amount of energy in food.