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
History of scuba diving before scuba became available. Jacques-Yves Cousteau, co-inventor of the first commercially successful open circuit scuba equipment, is claimed to have been the world's first open circuit scuba cave diver. Two regions have had particular influence on cave diving techniques and equipment due to their very different cave diving environments. These are the United Kingdom, and USA, mainly Florida. The number of sites where standard diving dress could be used is limited and there was little progress before the outbreak of World War II reduced the caving community considerably. The development of underwater warfare made a lot of surplus equipment available