Snorkeling
Snorkeling is swimming on the surface of the water, with the head and nose under the water, using a diving mask, snorkel, and diving fins. Scuba diving is swimming with the whole body underwater.  Scuba divers breathe through an oxygen tank, which allows them to breathe underwater for long periods at a time. Scuba divers also wear a tight diving suit, a diving mask, and diving fins.