Since the arrival of computer-generated animated movies, it's easy to forget cell animation. Until the dawn of CGI movies with releases like "Toy Story" and "A Bug's Life," the vast majority of animated films and shows were cell animated. This is the process in which every individual frame in the piece is drawn by hand. It is still, historically, the most popular of all forms of animation. The process itself is as intriguing as the work it produced.
The earliest cell-animated films date to the early 1900s. One of the first was by J. Stuart Blackton, with a piece called "Humorous phases of funny faces." His process was to draw funny faces on a blackboard, film one, erase it, draw another, and film that. While not quite the same, it can be considered an early form of cell animation. Walt Disney, one of the most famous animators in the world, started making films with his brother Roy in the 1920s. As the medium gained exposure, ensuing decades featured the release of popular titles including "Fantasia," "Snow White and the Seven Dwarfs" and "Dumbo." In 1995, Pixar and Disney Studios released "Toy Story," which was the first fully computer-generated animated film. After its massive success, the industry moved away from hand-drawn cell animation and into the realm of computer animation. Animation houses dedicated to traditional animation have dwindled in number.
Cell animation produces an entirely different look to computer-generated films. Because of the long and complicated process and the fact that frames are hand drawn, the argument is often made that traditional animation is much more personal than computer-generated animation. Hand-drawn animation also produced not just some of the best animated films of all time but some of the best films ever of any kind.
A common misconception is that every single detail in every frame in a cell-animated film is hand drawn. Often, a background "plate" is drawn. In other words, a few images of the background of a scene are drawn and used over and over so as to avoid having to redraw it. Also, images of specific character movements such as running can be used over and over again, with subtle changes, to avoid having to constantly draw the same thing.
Cell animation can often be easily identified by the quality of the animation. Because computer-generated animated pieces are drawn and rendered within a computer, they often appear to have three dimensions. Due to the nature of hand-drawing animation, cell-animated films appear to only have two dimensions. The colouring in a film is also an easy way to to identify it as hand drawn. The colour in a traditionally animated film is often applied with paint directly to the animation cell, giving it a very distinct look. As with everything about a computer-generated film, the colour is rendered by the computer, also giving it a very distinct look that is easily distinguishable from traditional animation.
The argument is often made that, due to an animator's interaction with every frame of a cell-animated project, this format is much more personal and unique than a computer-generated movie. Also, many of what are considered the best animated films of all time are products of the cell animation format.