Flicks

Animations and movies have much in common and a few differences; whereas movies are made of multiple images (frames) grouped in a video container file, animations in GIMP comprise multiple layers in a single image. In a movie, the frames follow in quick succession; in an animation, in layers.

The GIMP tool provides two variants for creating moving images: Either the new layer replaces the existing one (known as replace mode), or a new, transparent layer adds its content to the current image (combine mode). Movies often use a similar approach to reduce file size.