Oils for cooking are used to fry and sauté foods, for making salad dressings, and for use in baking. Oils are extracted from seeds and fruits such as corn, cottonseed, soybean, sesame, sunflower, safflower, olive, and avocado. Some oils are extracted from nuts such as peanut, walnut, almond, and hazelnut. There are two basic methods used for extracting the oil: cold extraction and heat extraction. Oils obtained from cold extraction may be cold pressed or vacuum extracted. The oils are flavorful and expensive, but tend to have lower smoke points than heat extracted oils. Heat extraction methods include expeller pressing and solvent extraction. The highly refined heat extracted oils usually lack color and flavor, but have a higher smoke point and longer shelf life than oils obtained through cold extraction.