<human>: What do I need to know about the different kinds of scuba diving?
<bot>: 
1. The three main types of scuba diving are open circuit, closed circuit and rebreather.
2. Open circuit scuba diving is the most basic type of scuba diving and involves breathing compressed air from a tank.
3. Closed circuit scuba diving uses a mixture of oxygen from the tank and exhaled air that is recycled through a demand valve.
4. Rebreather scuba diving uses a device called a rebreather which recycles exhaled gas back into the tank for reuse.