6)       Rendering

Rendering is the step that requires a computer(s) to calculate each of the frames within an animation.  For example there are 30 frames in one second of animation.  If the animation lasts 10 seconds, than there are 300 frames that need to be calculated by the computer.  Depending upon the complexity of the scene, each frame may take anywhere from 1 minute to 1 hour to calculate.  A 10-minute per frame render that lasts 10 seconds would involve 3000 minutes (50 hours) to calculate.  This would be spread over several computers in order to produce the animation within a reasonable time.