Classroom - where material is presented and reviewed

Swimming pool - where skills are taught and practiced in confined water

Open Water - where the student demonstrates the skills he or she has learned.

Typically, early open water training takes place in a local body of water such as a lake, a flooded quarry or a sheltered and shallow part of the sea. Advanced training mostly takes place at depths and locations similar to the diver's normal diving locations.

The usual sequence for learning most diving skills is to be taught the theory in the classroom, be shown the skill and practice in the pool using the minimum equipment, then practice again in open water under supervision in full equipment and only then use the skill on real dives.