Bollywood Animation Film is a method by which still figures are manipulated to appear as moving images. In traditional animation, images are drawn or painted by hand on transparent celluloid sheets to be photographed and exhibited on film. Computer animation can be very detailed 3D animation, while 2D computer animation (which may have the look of traditional animation) can be used for stylistic reasons, low bandwidth, or faster real-time renderings. The style takes inspiration from comic strips, often featuring anthropomorphic animals, superheroes, or the adventures of human protagonists. The illusion of animation—as in motion pictures in general—has traditionally been attributed to the persistence of vision and later to the phi phenomenon and/or beta movement, but the exact neurological causes are still uncertain.