A floor is the walking surface of a room or vehicle. Floors vary from in a cave to many-layered surfaces modern technology. Floors may be stone, wood, bamboo, metal, or any other material that can support the expected load.

In mathematics and computer science, the floor and ceiling functions map a real number to the largest previous or the smallest following integer, respectively. More precisely, floor(x) = is the largest integer not greater than x and ceiling(x) = is the smallest integer not less than x.