Open Water Diver (OWD) is an entry-level full diver certification for scuba diving. Although different agencies use different names, similar entry-level courses are offered by all diving agencies and consist of a combination of knowledge development (theory), confined water dives (practical training) and open water dives (experience).
The whole PADI training system.
The “Open Water Diver” certification name is used by the Professional Association of Diving Instructors (PADI),Scuba Schools International (SSI),the National Academy of Scuba Educators (NASE) Worldwide, and the Sub-Aqua Association (SAA),which is recognised by the Confédération Mondiale des Activités Subaquatiques (CMAS) as a CMAS 1-star certification.The National Association of Underwater Instructors (NAUI) entry-level course is called Scuba Diver. The British Sub-Aqua Club (BSAC) calls its equivalent qualification ‘Ocean Diver’.
The OWD level equals to the international Standard ISO 24801-2