Anime "Cel" (short for "Celluloid", セル画 in Japanese) is a transparent sheet of plastic used in the production of animation. Each frame of an animation is hand drawn and painted on the cel, placed over a background (often painted with watercolour) and photographed in sequence to create the vision of movement.

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While digital animation techniques have largely replaced the use of physical cels remains a popular collector's item among anime fans due to their historical significance and the unique, hand-crafted nature of each frame.