Cooking oil is purified fat of plant or animal origin, which is liquid at room temperature.

Some of the many different kinds of edible vegetable oils include: olive oil, palm oil, soybean oil, canola oil, pumpkin seed oil, corn oil, sunflower oil, safflower oil, peanut oil, grape seed oil, sesame oil, argan oil and rice bran oil. Many other kinds of vegetable oils are also used for cooking.

The generic term "vegetable oil" when used to label a cooking oil product refers to a blend of a variety of oils often based on palm, corn, soybean or sunflower oils.

Oil can be flavoured by immersing aromatic food stuffs such as fresh herbs, peppers and so forth in the oil for an extended period of time. However, care must be taken when using garlic and onions to prevent the growth of Clostridium botulinum (the bacteria that produces toxins that can lead to botulism) in this medium.