To give a provisional answer:

My dinky little Canon camera can shoot video. However, because of its flash memory, it can't shoot a whole lot at a time. So if I want to compile a video set to send to the family, I want to be able to edit together and join the little video files.

As I have learned the hard way, working with video is tricky, tricky, tricky. And the freeware tools aren't all they could be, probably because so many of the codecs are licensed and protected by shoals of legal sharks.