What is AIS (Automatic Identification System)?

A short range coastal tracking system used on ships and by Vessel Traffic Services (VTS) for identifying and locating vessels by electronically exchanging data with other nearby ships and VTS stations. Information such as unique identification, position, course, and speed can be displayed on a screen or an ECDIS. AIS is intended to assist the vessel's watch standing officers and allow maritime authorities to track and monitor vessel movements, and integrates a standardized VHF transceiver system such as a LORAN-C or Global Positioning System receiver, with other electronic navigation sensors, such as a gyrocompass or rate of turn indicator. The International Maritime Organization's (IMO) International Convention for the Safety of Life at Sea (SOLAS) requires AIS to be fitted aboard international voyaging ships with gross tonnage (GT) of 300 or more tons, and all passenger ships regardless of size. It is estimated that more than 40,000 ships currently carry AIS class A equipment.