Cell Animation, also written as Cel Animation, is the traditional hand-drawn animation technique in which each frame of movement is drawn individually on a transparent acetate sheet called a cel. The cels are then photographed in sequence over a painted background to create the illusion of motion. This process was the industry standard for animated film and television from the early twentieth century through to the late 1990s.

The name comes from the celluloid material the acetate sheets were originally made from. In a typical studio pipeline, lead animators would draw the key poses, and teams of in-between artists would fill in the intermediate frames to create smooth motion. Backgrounds were painted separately and reused across multiple frames where the environment remained static. Classic films from Disney, Warner Bros., and Studio Ghibli were produced using this method, and the distinctive look of cel animation, including its slightly textured quality, visible line weights, and limited frame rates, remains highly influential as an aesthetic reference.

In AI image and video generation, cel animation style is a widely used prompt descriptor that signals a desire for hand-drawn, traditionally animated aesthetics. It is useful for projects aimed at recapturing the warmth and craftsmanship of classic animation, and AI models have become increasingly capable of producing imagery that convincingly references this visual style.