Difference among classification survey, registration survey and under writers survey done by the classification society can be understood by following.

Registration is carried out by registers at the port of registry and each registrar is required to prepare a monthly return of the registrars and other current action on their register. Such information is to be submitted by the registrars to the officer in charge of the Ministry of Shipping. Before a ship can be registered it must be surveyed. This is done by a surveyor of ships duly appointed by the registering authority. The preparation of pre-registration survey is to establish an accurate description of ship for the registrar. This includes the vessels registered tonnage.

Apart from the official requirement of registration, almost all ocean going ships are classed and registered with one or other classification societies. Such registration is not compulsory but it is so advantageous that an un-classed ship is virtually non-existent now-a-days. In the absence of classification, a lot of difficulty would be experienced by underwriters, chartering brokers, bankers, merchants and shippers and others who have ready access to the latest and most reliable information regarding the ship in which they are interested. Ship owners would also be at a disadvantage if there existed no reliable organisation to check and certify whether their ships were considered, repaired and maintained in accordance with the highest prevailing standards and were in conformity with the international Regulations

Surveys undertaken by classification societies should not be confused with survey by the authorised representative of government for