Scuba diving

SCUBA is an acronym for "Self Contained Underwater Breathing Aparatus". In short, scuba diving is strapping a tank of air to your back out of which you can breathe air so you won't drown.

The mximum safe depth for use of normal scuba gear is between 30 and 50 metres, before nitrogen narcosis becomes a danger, even with Enriched Air Nitrox.

One global organization for Scuba Diving is PADI, who can be seen at http://www.padi.com/