For a great part of the history of Hollywood animation, the production of animated films was an exclusive industry that did not branch off very often into other areas. The various animation studios worked almost exclusively on producing animated cartoons and animated titles for movies. Only occasionally was animation used for other aspects of the movie industry. The low-budget "Superman serials" of the 1940s used animated sequences of Superman flying and performing super-powered feats which were used in the place of live-action special effects, but this was not a common practice.