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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: 50
  • Term
    Definition
  • Did you know?, Flag Semaphore, Signals & Communication Flag Semaphore Signals

    A system for conveying information at a distance through visual signals using hand-held flags.

    The position of the flags encodes the...

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  • General Nautical Terminology Flake

    To lay out or coil a line or rope in a flat, organised manner to prevent tangling or kinking.

    Flaking is a crucial technique in maritime...

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  • General Nautical Terminology Flaking a Line

    The process of neatly laying out a rope or line in a series of back-and-forth folds to prevent tangling and ensure it runs out smoothly when...

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  • General Nautical Terminology Flaking a Sail

    Flaking a sail is neatly folding or arranging it in parallel or accordion-like folds. This is typically done to store or stow the sail properly...

    More Details
  • General Nautical Terminology Flares

    A pyrotechnic device used on boats to signal distress or indicate position, especially in emergencies.

    Flares are an essential part of marine...

    More Details
  • General Nautical Terminology Flashing LightA light where there is more darkness than light
  • Flag Semaphore, Signals & Communication Letter F (Flag Semaphore)
    Letter F (Flag Semaphore)

    This shape represents the Letter F (Flag Semaphore) and the Number 6 (Flag Semaphore).

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

    International Morse Code sequence representing the letter F.

  • General Nautical Terminology, Navigation Flood Tide

    The incoming or rising phase of the tide, during which seawater flows landward and the water level increases. 

    A flood tide is the period...

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

    The flat, triangular blade or arm of an anchor designed to dig into the seabed and provide holding power.

    The term "fluke" in a marine context...

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  • General Nautical Terminology Flying Out

    The rapid and uncontrolled movement of a sail or line due to a sudden change in wind or tension.

    Flying out typically describes an event where...

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  • General Nautical Terminology, Signals & Communication FM

    A method of encoding information in a carrier wave by varying its frequency, commonly used in marine radio communications.

    Frequency...

    More Details
  • General Nautical Terminology Fo'c'sleThe part of the accommodation below the foredeck and forward of the mast
  • General Nautical Terminology FogVisibility reduced to less than 1000 metres (approximately 0.5 nautical miles)
  • General Nautical Terminology FoghornFog horns are used for sounding the appropriate sound signal whilst in restricted visibility
  • General Nautical Terminology Folding PropellerA propeller with folding blades, furling to reduce drag on a sailing vessel when not in use
  • General Nautical Terminology Following SeaSeas that are moving in the same direction as the vessel is heading
  • General Nautical Terminology Foot

    The lower edge of a sail, typically attached to the boom or deck of a sailing vessel.

    The term foot refers to the bottom edge of a sail. On a...

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

    The forward part of a vessel's deck, located towards the bow and often used for anchoring, mooring, or storage.

    The foredeck is a critical...

    More Details
  • General Nautical Terminology Forehatch

    A hatch located on the forward part of a vessel, typically providing access to the forepeak or forward compartments below deck.

    A forehatch is...

    More Details
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