Skates

Skates are similar to shoes but worn to perform the act of skating.

Ice skates were the first developed. Roller skates were mass produced in the 19th century. In-line skates did not become common until the late 20th century. Sneaker skates are shoes with roller wheels incorporated into them for dual purpose usage.

Modern ice skate blades are not shaped like knives. The bottom of the blade has a crescent-shaped hollow, creating two parallel sharp edges on each skate. The skater uses these edges in different combinations in order to maneuver. When ice skates are sharpened the blade is ground against a template that restores the hollow.