Understand the Sea,
From the Deck Up.
Navigation, the rules of the road, stability, safety and the career behind the rank, explained clearly for anyone who works, or wonders about, life at sea.
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All Pillars ›Find the Way
ECDIS, chart work, passage planning and position fixing.
The Road at Sea
The COLREGs: who gives way, lights, shapes and signals.
Float & Balance
Stability, GM, load lines and how ships are built.
Stay Alive at Sea
Man overboard, survival, GMDSS and life-saving gear.
Popular Guides
Browse All ›ECDIS Explained: What It Is and How It Works
The approved electronic chart system, from first principles to safe settings.
COLREGs: The Rules of the Road at Sea
The cornerstone of collision avoidance: conduct, lights and signals.
Parts of a Ship: A Beginner’s Tour of the Vessel
Bow to stern, keel to bridge: the anatomy of a ship, named and explained.
Man Overboard: Procedures & Recovery
The turns, the search, and the recovery: what to do the moment it happens.
Passage Planning: The Four Stages
Appraisal, planning, execution and monitoring, berth to berth.
Ship Stability Explained
Why ships stay upright: centre of gravity, metacentre and GM.
Browse the Glossary
Every term of the sea, defined in plain English and arranged A to Z, from ECDIS to the Williamson turn.
Open the Glossary ›Browse the Reference
Navigation & ECDIS
Where is the ship, and is the water ahead safe? That question is the whole of…
Explore ›Rules & Regulations
Most collisions are not accidents of fate but failures to apply rules every officer is supposed…
Explore ›Seamanship & Watchkeeping
A safe ship is the sum of watches kept well, hour after hour, long after the…
Explore ›Ships & Stability
A ship stays upright because of numbers, and capsizes when those numbers are ignored. This is…
Explore ›Safety & Survival at Sea
The equipment you hope never to touch is exactly the gear that has to work the…
Explore ›Off Watch
Time off watch is the rest of the sailor's life: the ports you actually remember, the…
Explore ›Life & Career at Sea
Going to sea is a career with its own ladder, its own paperwork, and its own…
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