Temperature

The way fats and oils behave at various temperatures plays a very important role in cooking. Fats are usually solids at room temperature and colder, while most oils behave as liquids. Thus knowing the melting point of a cooking oil will give you an idea of whether it will harden when added to the cool ingredients of a salad. Knowing the temperature at which a fat or oil will start to smoke indicates how much heat you can subject it to without affecting the flavor of the oil and whether it will work for a high-heat application like frying.