Uniregistry made a video explaining in brief what domain names are and how they can be bought and used.
In this video, Uniregistry explains the key components of domain names, from the top level to the second level, and the relationship between registries and registrars.
Here is the video from Uniregistry:
“The registry owns and controls the use, pricing, and requirements of every domain using their extension.” (00:32)