Scuba is a form of underwater diving in which a diver uses self-contained breathing apparatus and does not depend on surface air supplies. This allows greater freedom of movement and exploration, and enables longer dives than those of free divers. The equipment is generally carried in a scuba rig, which comprises a mask, snorkel and breathing tube, and a cylinder of compressed air or nitrox, used to provide the diver with breathing gas. Usually this is stored in a scuba tank, but it can also be inhaled from a rebreather.

When scuba diving you leave your text messages and to-do lists behind, immersing yourself in the magical world beneath the waves. You can discover shipwrecks and artificial reefs, or plunge into the deep sea’s caverns, chasms and walls.

There are many different scuba certification courses, from beginner open water to advanced open water and rescue diver. These usually involve theory classes and a lot of practice in a swimming pool to learn skills like breathing with your mouth closed, how to find and clear your regulator in the event of an emergency, and more.

Divers must also learn diving lingo, including hand signals to communicate with other divers. The most common is a thumbs up to indicate everything’s fine and a finger pointed down to say’something’s wrong’. During the slow ascent back to the surface, a scuba diver often makes a safety stop at a certain depth to ensure that they don’t change pressure too quickly and get nitrogen bubbles in their blood stream (narcosis or ‘the bends’) which can be fatal.