Also called celluloids, they are plastic sheets used in traditional animation by hand-drawing and coloring images (or frames) on individual sheets, then shooting them in a sequence and then adding voices, music and SFX in post-production to create the effect of animation. This method of animation has been replaced with computer animation, so cel-animated shows are not widely seen anymore. They will contain punched holes to allow them to be stacked and/or aligned by means of apeg bar. The edges of a cell typically have a telltale unfinished look with rough brush strokes and discontinued lines, as the edges of the cels are meant to be cropped out of the final work.
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