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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 & SeamanshipA great introduction to navigation and basic seamanship.
    • Day Skipper TheoryMany of the best skippers started their journey here.
    • Coastal Skipper / Yachtmaster® TheoryComing SoonEssential preparation for the Yachtmaster® practical exam.
    • SRC (VHF) Marine Radio CourseAn essential course for anyone intending to use a marine radio.
  • 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 nauctical, including marinas u0026 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 u0026 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 & SeamanshipA great introduction to navigation and basic seamanship.
    • Day Skipper TheoryMany of the best skippers started their journey here.
    • Coastal Skipper / Yachtmaster® TheoryComing SoonEssential preparation for the Yachtmaster® practical exam.
    • SRC (VHF) Marine Radio CourseAn essential course for anyone intending to use a marine radio.
  • 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 nauctical, including marinas u0026 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 u0026 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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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: 130
  • Term
    Definition
  • General Nautical Terminology ScopeAmount of cable or 'rode' which is let out when anchoring or laying a cable.
  • General Nautical Terminology, Nautical Saying Scupper

    An opening in the side of a ship or boat, designed to allow water on deck to drain overboard.

    In maritime terminology, a scupper is an...

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  • General Nautical Terminology Sea Anchor

    A device, typically a canvas or synthetic fabric drogue, deployed in the water to stabilise a vessel by creating drag and reducing drift in rough...

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  • General Nautical Terminology Sea BreezeA daytime wind blowing across a coastline from the sea caused by the rising air from land heated by the sun
  • General Nautical Terminology SeacockA stop-cock next to the hull to prevent accidental entry of water
  • General Nautical Terminology Sealegs

    The ability of a person to maintain balance and move steadily on a vessel in motion, particularly in rough seas.

    Sealegs is a term deeply...

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  • General Nautical Terminology, Safety Search and Rescue (SAR)

    The coordinated efforts undertaken to locate and assist individuals in distress or imminent danger, typically at sea, and to bring them to...

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  • General Nautical Terminology, Safety Search and Rescue Transponder (SART)

    An emergency device that responds to radar signals by transmitting a series of pulses to help rescuers locate a vessel or liferaft in...

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  • General Nautical Terminology, Navigation Secondary Port

    A location where tidal information is derived by applying corrections to data from a nearby Standard Port. 

    A secondary port is a coastal...

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  • Flag / Pennant, Signals & Communication Second Substitute (ICS Flag)

    Substitute or repeater flags allow messages with duplicate characters to be signalled without requiring multiple sets of flags.

  • General Nautical Terminology Sector Light

    Occasionally a light may not be visible through 360 degrees, or it may shine different colours depending on where it is viewed from. In this...

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  • General Nautical Terminology, Safety, Signals & Communication Sécurité

    A maritime safety message broadcast over radio to convey important but non-urgent navigational or weather-related information.

    Sécurité is a...

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  • Flag Semaphore, Morse Code, Signals & Communication Semaphore

    A signalling system used to convey information at a distance by means of visual signals, typically using flags or lights.

    Semaphore is a...

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  • General Nautical Terminology Semi-Displacement VesselA semi-displacement hull combines the features of a planing vessel along with a displacement hull. The vessel will rise at the bow as she... More Details
  • General Nautical Terminology SendVertical movement of waves or swell against, for example, a harbour wall
  • General Nautical Terminology, Navigation Set

    The direction which a current flows in a body of water.

    In marine navigation, understanding the set of a current is crucial for plotting an...

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  • General Nautical Terminology, Navigation Set

    The process of securing a boat in a stationary position by deploying and embedding an anchor into the seabed.

    When a mariner 'sets anchor',...

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  • General Nautical Terminology Set Sail

    To "set sail" means to begin a voyage or journey by sea, typically by hoisting the sails of a sailboat or ship to catch the wind and propel the...

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  • General Nautical Terminology Shackle

    A U-shaped metal fitting with a pin or bolt across the opening, used in marine applications to connect ropes, chains, or other fittings...

    More Details
  • General Nautical Terminology ShaftdriveMany sailing vessels and most motor cruisers will have a shaftdrive transmission system. A shaft runs from the gearbox, through the hull beneath... More Details
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