Calories (thermoc.)
A thermochemical calorie, often abbreviated as cal_th, is a unit of energy that is primarily used in the field of chemistry. It is defined as the amount of energy required to raise the temperature of one gram of water by one degree Celsius at a pressure of one atmosphere, precisely defined as 4.184 joules.
Calories
A calorie is a unit of energy often used in nutrition to quantify the energy content in food. Specifically, one calorie (cal) is defined as the amount of energy required to raise the temperature of one gram of water by one degree Celsius at a pressure of one atmosphere.