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 where a commemorative plaque was placed. During his lifetime, Jacques-Yves Cousteau received these distinctions: Cousteau's legacy includes more than 120 television documentaries, more than 50 books, and an environmental protection foundation with 300,000 members. Cousteau liked to call himself an "oceanographic technician." He was, in reality, a sophisticated showman, teacher, and lover of nature. His work permitted many people to explore the resources of the oceans. His work also created a new kind of scientific communication, criticized at the time by some academics. The so-called "divulgationism", a simple way of sharing scientific concepts, was soon employed in other disciplines and