Free-diving

Freediving (or free-diving) is a form of underwater diving that does not involve the use of scuba gear or other external breathing devices, but rather relies on a diver's ability to hold his or her breath until resurfacing. Examples include breath-hold spear fishing, freedive photography, apnea competitions, and to some degree, snorkeling. The activity that garners the most public attention is the extreme sport of competitive apnea in which competitors attempt to attain great depths, times, or distances on a single breath.