A salad is a serving in a meal that includes leaf vegetables such as lettuce, spinach, or arugula. Uncooked or cold cooked vegetables that are sliced into small pieces (for example tomato or onion) are then mixed with the leaf vegetables. A salad dressing or vinaigrette is then poured on top of the vegetables. Salad dressings and vinaigrettes are a mixture of oil, herbs, spices, and flavorings. Some people also add other foods to the salad, such as croutons, bacon, chicken, grated cheese, tuna, pasta, olives, cooked potatoes, rice, or beans.