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Nautical Know How
  • Our Courses

      All our courses are engaging, interactive and fun! Whether formal training or simply looking to brush up, we take online learning to the next level.

      • Sailing EssentialsFreeA free course great for anyone who spends time on the water.
      • Essential Navigation & SeamanshipRYA course for beginners. Learn charts, tides, pilotage, and core seamanship with simple practice tasks.
      • Day Skipper TheoryMost PopularRYA course for inshore skippers. Plan day passages using chartwork, tides, weather, and COLREGs.
      • Coastal Skipper / Yachtmaster® TheoryComing SoonRYA course for advanced navigation and passage planning. Work with secondary ports, tidal streams, and offshore weather.
      • SRC (VHF) Marine Radio CourseRYA Short Range Certificate radio course. Study online, then take the practical exam with an RYA assessor.
  • Directory

      Are you looking for something nautical related? Our directory is an extensive list of courses and places associated with the marine industry. Hop over and search now.

      • Places
        Find anywhere nautical, including marinas & training centres. If it exists, we’ve got it listed!
      • Courses
        We help you navigate through the complex world of training and help find what’s best for you.
  • Know-How

      We believe every day’s a school day on a boat! That’s why we built Nautical Know-How, dedicated to answering your questions. Even better, if it can’t answer your question immediately, you can request it, and we’ll add it to our knowledge base.

      • Nautical Terms & Terminology
        Understanding the language of the marine world is like trying to learn a pirate’s secret code while juggling fish. Let us explain why a sheet isn’t for your bed, why “heave ho” doesn’t mean throw up (most of the time), and why “dead reckoning” is surprisingly less ominous than it sounds.
      • Why do we have tides?
        Have you ever wondered what causes the tides? Check out this video, which introduces the forces that create the tides we experience on Earth.
      • What causes our weather?
        A video introducing the drivers behind our weather, part of our RYA Day Skipper & RYA Coastal Skipper / Yachtmaster® Offshore theory courses.
      • Buoyage Flashcards
        Flashcards designed to help remember the buoys in the IALA system. If you want to learn them in detail, our module ‘Getting in and out of harbour‘, covers the IALA system and different buoys used.
      • Interactive Rule Book (COLREGs / IRPCS)
        Whether you’re a novice sailor or a seasoned skipper, we can help you navigate the IRPCS confidently and clearly. Our easy-to-use, easy-to-understand, plain English rule book with helpful interpretations of what each rule means.
      • The Salty Sea Blog
        From salty old sea dogs to fresh-faced deckhands, this blog is for anyone who finds peace, adventure, and a bit of mischief on the water. So hoist the main, set your course, and let’s sail into the stories, lessons, and musings that make life on the sea so irresistible.
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Nautical Know How
  • Our Courses

      All our courses are engaging, interactive and fun! Whether formal training or simply looking to brush up, we take online learning to the next level.

      • Sailing EssentialsFreeA free course great for anyone who spends time on the water.
      • Essential Navigation & SeamanshipRYA course for beginners. Learn charts, tides, pilotage, and core seamanship with simple practice tasks.
      • Day Skipper TheoryMost PopularRYA course for inshore skippers. Plan day passages using chartwork, tides, weather, and COLREGs.
      • Coastal Skipper / Yachtmaster® TheoryComing SoonRYA course for advanced navigation and passage planning. Work with secondary ports, tidal streams, and offshore weather.
      • SRC (VHF) Marine Radio CourseRYA Short Range Certificate radio course. Study online, then take the practical exam with an RYA assessor.
  • Directory

      Are you looking for something nautical related? Our directory is an extensive list of courses and places associated with the marine industry. Hop over and search now.

      • Places
        Find anywhere nautical, including marinas & training centres. If it exists, we’ve got it listed!
      • Courses
        We help you navigate through the complex world of training and help find what’s best for you.
  • Know-How

      We believe every day’s a school day on a boat! That’s why we built Nautical Know-How, dedicated to answering your questions. Even better, if it can’t answer your question immediately, you can request it, and we’ll add it to our knowledge base.

      • Nautical Terms & Terminology
        Understanding the language of the marine world is like trying to learn a pirate’s secret code while juggling fish. Let us explain why a sheet isn’t for your bed, why “heave ho” doesn’t mean throw up (most of the time), and why “dead reckoning” is surprisingly less ominous than it sounds.
      • Why do we have tides?
        Have you ever wondered what causes the tides? Check out this video, which introduces the forces that create the tides we experience on Earth.
      • What causes our weather?
        A video introducing the drivers behind our weather, part of our RYA Day Skipper & RYA Coastal Skipper / Yachtmaster® Offshore theory courses.
      • Buoyage Flashcards
        Flashcards designed to help remember the buoys in the IALA system. If you want to learn them in detail, our module ‘Getting in and out of harbour‘, covers the IALA system and different buoys used.
      • Interactive Rule Book (COLREGs / IRPCS)
        Whether you’re a novice sailor or a seasoned skipper, we can help you navigate the IRPCS confidently and clearly. Our easy-to-use, easy-to-understand, plain English rule book with helpful interpretations of what each rule means.
      • The Salty Sea Blog
        From salty old sea dogs to fresh-faced deckhands, this blog is for anyone who finds peace, adventure, and a bit of mischief on the water. So hoist the main, set your course, and let’s sail into the stories, lessons, and musings that make life on the sea so irresistible.
  • Chandlery
Sign In Join now—it’s Free

Glossary

AJAX progress indicator
Nautical chart abbreviations are like the secret code of the seas—except instead of buried treasure, they lead to rocks, buoys, and mysterious dashed lines that scream, 'Don’t sail here.' Learning them can feel like cracking a pirate’s encrypted diary, but don’t worry, matey! With clever tools, quirky mnemonics, and a splash of humour, we’ll help you go from 'What’s "FOUL" mean? to confidently navigating the “Wk” wrecks and “Fl G” flashes like a salty sea captain. Think of it as Rosetta Stone, but for avoiding sandbanks!
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Results: 1149
  • Term
    Definition
  • General Nautical Terminology Bi-colour LightCombined red (port) and green (starboard) light positioned on the bow
  • General Nautical Terminology Bight

    A loop created in the standing part of a rope.

  • General Nautical Terminology Bilge PumpUsed to empty unwanted water from the vessel. Can be automatic, manual and mobile and are usually positioned to collect the water from the lowest... More Details
  • General Nautical Terminology BilgesThe compartment at the bottom of the hull of a ship or boat where water collects and must be pumped out of the vessel.
  • General Nautical Terminology Bimini

    A canvas or fabric top supported by a metal frame, typically found on boats to provide shade and protection from the sun. 

    A Bimini is a...

    More Details
  • General Nautical Terminology BinnacleThe stand on which the ship's compass is mounted, usually in front of the wheel. May also carry navigation instruments.
  • General Nautical Terminology, Weather (Meteorology) Biscay

    Sea area of the Met Office Shipping Forecast. Covers the Bay of Biscay, off the west coast of France and north coast of Spain.

    Covering the Bay...

    More Details
  • Flag Semaphore, Signals & Communication Letter B (Flag Semaphore)
    Letter B (Flag Semaphore)

    This shape represents the Letter B (Flag Semaphore) and the Number 2 (Flag Semaphore).

  • Morse Code, Signals & Communication Letter B (Morse Code)

    International Morse Code sequence representing the letter B.

  • General Nautical Terminology Block

    A type of pulley system used to change the direction of a line, rope, or cable on a boat. Blocks consist of one or more grooved wheels, called...

    More Details
  • General Nautical Terminology Boat HookA pole with a hook on the end, used to reach into the water to catch buoys or other floating objects.
  • General Nautical Terminology Boat WindJust like running down the road or cycling downhill you will feel the wind on your face; boat wind is just the same. As the boat moves through the... More Details
  • General Nautical Terminology BollardStrong fitting, firmly bolted to the deck, to which mooring lines are made fast. Large bollards are on quays, piers and pontoons
  • General Nautical Terminology Boom

    A horizontal spar used to extend the foot of a sail and control its angle to the wind. 

    A boom is an essential part of a sailing vessel's...

    More Details
  • General Nautical Terminology Boom OutOn a run to thrust the Genoa out to windward so that it fills with wind
  • General Nautical Terminology, Weather (Meteorology) Bora

    A strong, cold, and dry northeasterly katabatic wind that blows from the land to the sea, particularly along the eastern Adriatic coast.

    The...

    More Details
  • Did you know?, General Nautical Terminology Bosun

    Short for boatswain, the Bosun is a senior crew member responsible for the vessel's maintenance, repair, and overall operation. The bosun...

    More Details
  • General Nautical Terminology, Parts of a Boat Bow

    The forward part of a vessel, designed to cut through the water and reduce resistance.

    The bow of a vessel is its frontmost section, typically...

    More Details
  • General Nautical Terminology Bow Line

    A rope used to secure the bow of a vessel to a dock or another fixed object.

    A bow line is a critical part of a vessel's mooring system,...

    More Details
  • General Nautical Terminology, Knot Bowline

    A type of knot used to form a fixed loop at the end of a rope, commonly employed in maritime settings for securing or towing.

    The bowline is...

    More Details
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