Big name:
Calorie (Cal for short), transliterated from English Calorie, is defined as the heat required to raise water 1℃ at1atmospheric pressure. Calorie is an energy unit, which is still widely used in nutrition measurement and fitness manual. The international standard unit of energy is joule.
Calories, also known as capital letter C, are most commonly used in food labels, which is equivalent to the heat required to raise 1 000 grams of water from 14.5℃ to 15.5℃ at1atmospheric pressure, which is about equal to the internal energy of 4 186 joules.