https://www.techradar.com/news/best-action-camera

Action cameras are unlike any other kind of camera. They're designed to be attached to helmets, surfboards, cars and other objects, and they're small, tough and simple to operate, with a lens that captures the world in high-definition video and in a wide-angle fish-eye perspective.

Their small size and dramatic POV ('point of view') footage has made them popular with extreme sports participants, who capture their adventures by attaching cameras to themselves or their equipment. They're also used by TV production companies where using a regular video camera would be impossible.