Waldorf salad is a classic American salad made with apples, celery, grapes, and walnuts. It was created at the Waldorf-Astoria Hotel in New York City in the late 19th century. The salad is dressed with mayonnaise and lemon juice, which adds a creamy and tangy flavor. Waldorf salad is a sweet and crunchy salad that is often served as a side dish or a light lunch.