Birkenstock Essentials Arizona Slide Sandal – A slider is actually a type of footwear different from shoes and similar to flip-flops. They are backless and open-toed, primarily an open-toed mule. Usually, all slides are sandals. Thongs and flip flops are usually categorized separately. Slides could be high-heeled, flat-heeled or somewhere between, and could cover approximately the whole foot from ankle to toe, or can have only a few narrow straps. They sometimes consist of a single strap or maybe a sequence of straps across the toes and the lower half of the foot to carry the shoe to the foot.