Nautical

Seamanship is the art of operating a ship or boat.

It involves topics and development of specialised skills including: navigation and international maritime law; weather, meteorology and forecasting; watchstanding; ship-handling and small boat handling; operation of deck equipment, anchors and cables; ropework and line handling; communications; sailing; engines; execution of evolutions such as towing; cargo handling equipment, dangerous cargoes and cargo storage; dealing with emergencies; survival at sea and search and rescue; and fire fighting.

The degree of knowledge needed within these areas is dependent upon the nature of the work and the type of vessel employed by a mariner.

Navigation is the art and science of safely and efficiently directing the movements of a vessel from one point to another. Piloting uses water depth and visible references, while dead reckoning uses courses and distances from the last known position. More than just finding a vessel's present location, safe navigation includes predicting future location, route planning and collision avoidance. Nautical navigation in western nations, like air navigation, is based on the nautical mile. Navigation also includes electronics such as GPS and Loran (Long Range Navigation). Celestial navigation involves taking sights by sextant on the planets, moon, stars, sun and using the data with a nautical almanac and sight reduction tables to determine positions. Accurate time information is also needed. After nautical dusk, navigation at sea referencing the horizon is no longer possible, and after nautical dawn such navigation again becomes possible.

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