Scuba diving is a sport where people breathe underwater. It is usually done for recreational purposes, but some divers go down to deep depths for commercial, scientific, or military purposes.

Diving has been practiced since ancient Greece. Early Greeks used hollow plant stems in their mouths to breathe. In the 16th and 17th centuries, diving bells were developed to allow the diver to stay underwater for longer periods of time. These bells were also used for dock work.

The first modern-day scuba regulator was invented by Jacques Cousteau and Emile Gagnan in 1942. The open-circuit scuba system was modeled after a simple ambient pressure supply valve apparatus.

The first open-circuit scuba system was hooked up to a 0.7 gallon tank with air compressed to 2,100 psi. Because of the low pressure of the air, the scuba diver had to hold his breath for a period of time to get the needed oxygen.

This led to a dangerous medical condition, decompression sickness. Eventually, a demand regulator was developed that would give a diver oxygen only when he or she inhaled.

A buoyancy control device is also required. Divers can fill it with air or a secret air bladder to keep them neutrally buoyant underwater.

If you want to take up scuba diving, you can attend a course in the equipment and skills required to dive safely. Most courses teach basic skills such as how to navigate underwater, how to use breathing equipment, and safety. There are also advanced diving courses for experienced divers.