A salad is a dish consisting of a mixture of small pieces of food, which may be mixed with a sauce or salad dressing. They are typically served cold, although some, such as south German potato salad, are served warm. Salads may contain vegetables, fruits, cheese, cooked meat, eggs, grains and nuts. Garden salads use a base of leafy greens like lettuce, arugula, kale or spinach; they are common enough that the word salad alone often refers specifically to garden salads. Other types include bean salad, tuna salad, fattoush, Greek salad, and Japanese sōmen salad (a noodle-based salad). The sauce used to flavor a salad is commonly called a salad dressing; well-known types include ranch, Thousand Island, and vinaigrette. Vinaigrette comes in many varieties; one version is a mixture of olive oil, balsamic vinegar, herbs, and seasonings.