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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, Navigation, Safety VTS

    A shore-based system that monitors and manages vessel movements in busy or hazardous waterways to enhance safety, efficiency, and environmental...

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  • General Nautical Terminology WakeTurbulence behind a vessel. Not to be confused with wash
  • General Nautical Terminology, Parts of a Boat Warp

    A strong rope or line used for mooring, towing, or manoeuvring a vessel, particularly in situations requiring precise control. 

    Warping is a...

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  • General Nautical Terminology WashThe waves created by a vessel. Not to be confused with wake.
  • General Nautical Terminology, Parts of a Boat Wash Boards

    Removable boards or panels used to close off the companionway of a boat to prevent water from entering the cabin.

    Wash boards are an essential...

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  • General Nautical Terminology Watch

    A designated period during which a specific crew member or group is responsible for the safe operation and navigation of the vessel.

    In...

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  • General Nautical Terminology Waterline lengthThe length of the vessel at the point where it sits in the water. It excludes the total length of the boat, such as features that are out of the... More Details
  • General Nautical Terminology, Navigation Water Track

    The vessel’s course through the water, derived from the compass course steered, allowing for leeway but not tide. A line representing the water...

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  • General Nautical Terminology Way

    Speed, progress, or momentum through the water. More technically, the point at which there is sufficient water flow past a vessel's rudder for it...

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  • General Nautical Terminology, Navigation Waypoint (WPT)

    A specific location or reference point on a navigational route, often used to mark progress or changes in course.

    A waypoint is a...

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  • Flag / Pennant, Signals & Communication Code Flag Whiskey (W)

    The International Maritime Signal Flag Whiskey.

    Meaning

    I require medical assistance.

  • General Nautical Terminology Weather Helm

    The tendency of a sailing vessel to turn windward (towards the wind) when under sail, requiring corrective steering to maintain a desired...

    More Details
  • General Nautical Terminology Weigh Anchor

    To lift the anchor from the seabed in preparation for setting sail or moving a vessel.

    Weighing anchor is a fundamental nautical action that...

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  • General Nautical Terminology, Navigation WGS84

    A standard in satellite-derived positions. Charts will indicate if they are calibrated to WGS84 or another system.

    WGS84 is the standard...

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  • General Nautical Terminology WheelThe wheel is used to steer the vessel. This yacht has two wheels so that the helmsman or woman has a clear view up either side of the vessel.
  • General Nautical Terminology Whipping

    To bind the end of a rope with small cord or twine to prevent it from fraying.

    Whipping is a traditional and essential technique in ropework,...

    More Details
  • General Nautical Terminology WhiskerLight spar to hold out the clew of a headsail when running, particularly when goosewinged
  • Did you know?, Phonetic Alphabet, Signals & Communication Whiskey

    Pronounced: WISS-key

    The term for the letter W in the NATO Phonetic Alphabet.

  • General Nautical Terminology White HorsesBreaking waves with foamy crest. Not surf breaking on the shore
  • General Nautical Terminology, Weather (Meteorology) Whole Gale

    Beaufort Scale – Force 10

    A Whole Gale is a term used in meteorology to describe a wind of force 10 on the Beaufort scale, corresponding to...

    More Details
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