Belly boarding is probably most people's first taste of surfing. The bellyboard is much shorter than a surfboard and thinner than a boogie board.
It's made out of wood and is about four feet tall with a curve at the top end.
Riders use the white water to come into the beach - unlike surfers and boogie boarders they don't go out of their depth.
The tenth World Bellyoarding Championships are being held on Sunday at Chapel Porth in North Cornwall. It started off with a handful of people but now has entrants from around the world.
This stunning footage shows early a family enjoying some bellyboarding action in Cornwall during the 1940s.
Credit: South West Film & Television Archive