Pre-rendering

Pre-rendering is the process in which video footage is not rendered in real-time by the hardware that is outputing or playing back the video. Instead, the video is a recording of a footage that was previously rendered on a different equipment (typically one that is more powerful than the hardware used for playback). Pre-rendered assets (typically movies) may also be outsourced by the developer to an outside production company. Such assets usually have a level of complexity that is too great for the target platform to render in real-time.

The term pre-rendered describes anything that is not rendered in real-time. This includes content that could have been run in real-time with more effort on the part of the developer (e.g. video that covers a large number of a game's environments without pausing to load, or video of a game in an early state of development that is rendered in slow-motion and then played back at regular speed). The term is generally not used to describe video captures of real-time rendered graphics despite the fact that video is technically pre-rendered by its nature. The term is also not used to describe hand drawn assets or photographed assets (these assets not being computer rendered in the first place).

Read more about Pre-rendering:  Advantage and Disadvantage, Usage, Other Methods