Salad dressing is a condiment used to enhance the flavor of salads. It is usually made from a combination of OIL, vinegar, and herbs or spices. Two of the most popular salad dressings are MAYONNAISE and mayo. MAYONNAISE is a thick, creamy sauce made from egg yolks, OIL, and vinegar. Mayo is a lighter version of MAYONNAISE that is made with OIL, vinegar, and seasonings. OIL is also an important ingredient in salad dressing, as it helps to emulsify the other ingredients and give the dressing a smooth texture.