Animation is the simulation of movement through a series of images or frames.
Before computers came into the picture, animation was created using traditional techniques such as hand-drawn animation and stop-motion animation (or model animation). Hand-drawn animation, as the name suggests, involves hand-drawn scenes on paper. Each scene is repeated on the next sheet of paper with a slight change in the scene. All the papers are put together in sequence and the pages are turned very quickly, like a flipbook. The slight changes on the sheets of paper create 2D animation, and this can be filmed into a motion film. This technique is used very often in Disney cartoons and movies. As you can imagine, this is a very time-consuming way to produce animation, as you would need thousands of drawings to create seconds of the film.
Stop-motion animation involves creating models, moving them a little in each frame to mimic movement, and filming this sequence to construct an entire scene...