It's a fairly minimalistic, but self-contained, 3D printer. You might want to use it to "repstrap" a replacement printer at some point -- but you at least start with a basic set of electronics, motors, rods, and bearings.
Toward the end of the video, you can see the high-test line that is used instead of the more conventional belts.
Lacking a heated bed, the Simple should only be used with PLA filament (1.75mm). However, it could certainly be used to print parts for making a more fully capable printer. As long as you don't push its performance envelope, it should be a pretty nice printer for the price!