Animation is a technique that creates the appearance of motion in a series by photographing consecutive illustrations, figures, or even puppets to produce the illusion of movement. Since the human brain can only keep track of one image at a time, when many images flash by too quickly, the brain combines them into a single moving picture.
Drawings or paintings are made on celluloid sheets, then photographed to create conventional types of animation. It may be seen in early cartoons, but CGI has now replaced traditional animation methods for making animated films.