Buddy diving just before and after the Second World War. After the invention of the "aqualung" by Cousteau and Gagnan, the first commercially underwater breathing apparatus became available for sale for sporting purposes in the late 1940s. As the new sport of scuba diving rapidly expanded through the 1950s, several sporting organisations—notably the YMCA—began programmes to train swimming enthusiasts in this new aquatic pastime, and began to codify what they believed were proper practises for this expanding sport. The YMCA considered the buddy system a useful corollary to the "never swim alone" rule of their swimming and lifesaving programmes. Cousteau himself independently
Jacques Cousteau center of the strait, and the porpoises followed for a few minutes, then diverged toward mid-channel again. It was evident that they knew where the optimal course lay, even if the humans did not. Cousteau concluded that the cetaceans had something like sonar, which was a relatively new feature on submarines. In 1954, Cousteau conducted a survey of Abu Dhabi waters on behalf of British Petroleum. Among those accompanying him was Louis Malle who made a black-and-white film of the expedition for the company. Cousteau won the Palme d'Or at the Cannes Film Festival in 1956 for "The Silent World"