Skin Divers

Freediving, free-diving, free diving, breath-hold diving, or skin diving is a form of underwater diving that relies on divers' ability to hold their breath until resurfacing rather than on the use of a breathing apparatus such as scuba gear.

Besides the limits of breath-hold, immersion in water and exposure to high ambient pressure also have physiological effects that limit the depths and duration possible in freediving.

Examples of freediving activities are: traditional fishing techniques, competitive and non-competitive freediving, competitive and non-competitive spearfishing and freediving photography, synchronized swimming, underwater football, underwater rugby, underwater hockey, underwater target shooting and snorkeling. There are also a range of "competitive apnea" disciplines; in which competitors attempt to attain great depths, times, or distances on a single breath.

Historically, the term free diving was also used to refer to scuba diving, due to the freedom of movement compared with surface supplied diving.

In ancient times freediving without the aid of mechanical devices was the only possibility, with the exception of the occasional use of reeds and leather breathing bladders. The divers faced the same problems as divers today, such as decompression sickness and blacking out during a breath hold. Freediving was practiced in ancient cultures to gather food, harvest resources such as sponge and pearl, reclaim sunken valuables, and to help aid military campaigns.

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