Slide is a common term that refers to a shoe that is backless and open-toed, essentially an open-toed mule. Generally, all slides are a type of sandal. Thongs and flip flops are normally classified separately. Slides can be high-heeled, flat-heeled or somewhere in between, and may cover nearly the entire foot from ankle to toe, or may have only one or two narrow straps. They usually include a single strap or a sequence of straps across the toes and the lower half of the foot to hold the shoe on the foot. The term is descriptive in that this shoe is easy to 'slide' on and off the foot when the wearer wants to do so.