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Short explainers of the terms this site uses, written in plain language and linked from the places where the terms matter. They define words; they do not carry data, so nothing here needs a source line.
Terms
AISAIS is the radio system ships use to broadcast their identity and position. Public ship tracking statistics are built from it.Blank sailingA blank sailing is a scheduled ship departure that a carrier cancels, usually to match capacity to weaker demand.ChokepointA chokepoint is a narrow canal, strait or cape that a large share of shipping must pass through, which is why one incident there can ripple across trade.Draft restrictionA draft restriction limits how deep a ship may sit in the water, so it can carry less cargo through a canal or shallow channel.Force majeureForce majeure is a contract clause that excuses a party from obligations when an extraordinary event outside its control prevents performance.LashingLashing is securing containers on a ship's deck with rods and locks. Lashers work at the quayside, so a lashing strike can stop a terminal.Port callA port call is one visit by a ship to a port. Counting port calls is how we measure how busy a port is from day to day.TEUA TEU, or twenty-foot equivalent unit, is the standard way to count container capacity and volume. A forty-foot container is two TEU.TransitA transit is one vessel passing through a chokepoint such as a canal or strait. It is the unit we count for chokepoints.