Film perforations, also known as
perfs, are the holes placed in the
film stock during manufacturing and used for transporting (by
sprockets and claws) and steadying (by
pin registration) the
film. Films may have different types of perforations depending on
film gauge,
film format, and intended usage. Perforations are also used as a standard measuring reference within certain camera systems to refer to the size of the
frame.