The tradition goes back all the way to the earliest days of animation with Winsor McCay's short Gertie the Dinosaur, which shows a live-action narrator (specifically, a "live" actor, instead of a filmed one) interacting with an animated landscape and character (Gertie). In one scene, the narrator appears to throw a real orange which is caught by Gertie (the real orange is replaced by an animated one just as it leaves the narrator's hand), and the film climaxes with a scene in which the narrator enters the animated landscape (again, replaced by an animated version) and takes a ride on the famous dinosaur's back.
In the later days of silent film, the popular animated cartoons of Max Fleischer included a series where his cartoon character Koko the Clown interacted with the live world; for example, having a boxing match with a live kitten. In a variation on this concept, Walt Disney's first directorial efforts (years before Mickey Mouse was born) were the animated Alice Comedies short cartoons, in which a young live-action girl named Alice interacted with animated cartoon characters.
In the era of sound film, the 1940 Warner Bros. cartoon You Ought to Be in Pictures, directed by Friz Freleng, can be seen as a predecessor to Roger Rabbit. The animated sequence in the 1945 film Anchors Aweigh in which Gene Kelly dances with an animated Jerry Mouse is one of the actor's most famous scenes.
The Disney Studio mixed live-action and animation in several notable films (which are primarily considered live-action):
With the commercial and technological success of Who Framed Roger Rabbit, a number of live-action/animated films followed, including Cool World, Space Jam, and Looney Tunes: Back in Action - though none of them have had any major commercial success equal to Roger Rabbit.
There were also many previous films combining live action with stop motion animation using back projection, such as the films of Willis O'Brien and Ray Harryhausen in the United States, and Aleksandr Ptushko, Karel Zeman and more recently Jan Švankmajer in Eastern Europe. The first feature film to do this was The Lost World (1925). In the 1935 Soviet film The New Gulliver, the only character who wasn't animated was Gulliver himself. See also: List of stop-motion films
The combination of live action and animation is very common in TV commercials, especially those promoting products appealing to children.
Live-action can also means that a film or a show is adapted from an anime, manga, or comics. Example of this show that are adapted from manga are Death Note and Great Teacher Onizuka. The show that are adapted from anime are Speed Racer and Dragonball. The shows that are adapted from comics are from Marvel comics such as Spider-Man, X-Men, and Fantastic Four. DC Comics such as Superman and Batman are also adapted into live-action films.
Originally, animation was combined with live action in several ways, sometimes as simply as double-printing two negatives onto the same release print. More sophisticated techniques used optical printers or aerial image animation cameras, which enabled more exact positioning, and better interaction of actors and animated characters. Often, every frame of the live action film was traced by rotoscoping, so that the animator could add his drawing in the exact position.
In the penguin sequence in Mary Poppins, they filmed the live action part first, having the actors sitting in front of a painted background. Then the penguins were added, probably by using cel overlay.
With the rise of digital special effects, combining live-action and animation has become more common. The Star Wars prequels and the Lord of the Rings trilogy, for example, include substantial amounts of animation, though it may not be recognized as such because of the animation's realistic, non-cartoony appearance.