My reference

PADI courses outline

http://www.padi.com/scuba-diving/padi-courses/course-catalog/

Scuba Gear introduction

http://www.padi.com/scuba-diving/padi-courses/course-catalog/about-scuba-gear/

Scuba Diving diver course test

http://www.atlasandboots.com/how-to-pass-padi-open-water-diver/

Scuba Diving Theory

http://scuba.about.com/od/Theory/

Scuba Diving simulation Reference

http://ediving.us/simulators.php