General purpose ratings are the trainees on board merchant ship who undergoes short training program which is generally designed in 2 phases (Pre-sea & On Sea training).They are trained to work in both the departments Deck and Engine and that is the reason they are called General Purpose. Ratings can be a part of deck or engine room assisting the officers and engineers for the deck and engine operations. After the completion of pre sea training the seaman can decide that whether he wants to be a part of deck or engine team. Eventually they become the certified watch keeper in deck or engine room. Ratings once complete 36 months of sea time can also undergo post sea course and qualify examination in India/UK/Australia/Singapore and become deck or engineer officer, but for that a lot of hard work and determination is required from their end.