a code placed within an advertisement or coupon so that an inquiry, coupon return, order, or other response can be traced to a specific ad or publication; the code may be a variation in address, a number, a letter, or some other such identification. Useful in testing to determine which headline, appeal, layout, or publication, for example, generated the most responses.

A number put along the edge of the film that identifies each exposed frame. Also known as edge code. Edge code refers to frame counting codes found on the film edge. May be either the latent key numbers used by Cinema Tools or ink numbers added to the edge of workprints. Key numbers are typically superimposed by the telecine onto the edge of the video frames. Cinema Tools uses key numbers to help match digital edits back to the original camera negative. Key numbers consist of a key prefix, which is unchanging throughout an entire roll of film, and a frame number, which consists of a footage number and a frame count number. It also often has a frame type identifier. For example, in the key number KJ 291010 5867 +07 B, the key prefix is KJ 291010, the frame number is 5867 +07, and the frame type identifier is B.

See EDGE NUMBER.