Kata are the pre-arranged sets of movements in which the karateka defends against several imaginary attackers. Each movement of a kata represents a self-defense technique against a potential opponent. These self-defense "applications" are traditionally called bunkai (analysis). All kata have an embusen, or performance line. This is the path of the kata, or rather, its floor plan. The movements of a given kata must always be performed in the correct order, and the kata must always start and finish on the same spot.