Automatic Identification System, a tracking system that uses VHF radio transponders on ships to automatically exchange vessel identification, position, course, speed, and other data with nearby ships and shore-based systems. AIS is mandatory for vessels of 300 gross tonnage and above on international voyages under SOLAS.
Also known as: Automatic Identification System.
Category: Safety & Emergency
On The Maritime
The desks where this concept is measured.
In the Glossary
Automatic Identification SystemAIS
A VHF transponder system that broadcasts a ship’s identity, position, course and speed for collision avoidance and tracking.
Read the full explanation in the GlossaryRelated terms
More in Safety & Emergency
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Back to DictionaryEntry updated May 2026