The art of animation started with the cavemen who used to draw pictures on the rock surfaces. Though animation was formally demonstrated in 1828 by a Frenchman, Paul Roget, the first animated film Humorous phases of funny faces by J. Stuart Blackton was made in 1906 by drawing comical faces on a blackboard, photographing them, and then erasing it to draw another stage of the facial expression. It was in 1914, that the first cartoon named Gertie, the Dinosaur by Winsor McCay, consisting of 10,000 drawings, was shown as a film in the theaters. In the early twenties, traditional animation techniques were developed and more sophisticated cartoons were produced. It was during this time that Warner Bros and Walt Disney studios came to exist. Computer animation, started during seventies and eighties, had a greater impact and with the passage of time, more and more advanced techniques were developed.