Generally speaking, there are two kinds of calories:
Calories, also known as capital letter C, are equivalent to the heat required to raise 1 000g of water from 14.5℃ to 15.5℃ at1atmospheric pressure, which is about equal to the internal energy of 4 186 joules.
Small card, also known as cal, is common in scientific research literature, 1000 small card = 1 big card (1 card).
Extended data:
Calorie (Cal for short), transliterated from English Calorie, is defined as the heat required to raise 1 gram of water to 1 degree Celsius at 1 atmospheric pressure.
Nutrition measurement and fitness manuals are still widely used, and the international standard unit of energy is Joule.