Motion Detection= Refers to the feature in some NVRs and DVRs to only record video if something in the image moves or changes. Therefore you don’t have to look through hours of stored video looking for something to happen. It also saves a lot of space on the hard drive, and allows you to record at a much lower frame rate when nothing is happening. When the system detects motion, the cameras can be kicked up to record at a higher frame rate (FPS).