Contemporary buoyancy compensator designs have an array of special features that can turn an ordinary buoyancy compensator into an extremely helpful adjunct to the diver's gear. (…)

Buoyancy compensator devices are used to aid the scuba diver to maintain neutral buoyancy. (…)

A buoyancy compensator (BC) or buoyancy compensating device (BCD) is a jacket that helps divers maintain neutral buoyancy during a dive.
When an object underwater rises, it's positively buoyant. (…)

Before entering the water it's a good idea to learn a little very elementary physics. (…)