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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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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: 57
  • Term
    Definition
  • General Nautical Terminology Angle of Vanishing Stability (AVS)

    The Angle of Vanishing Stability (AVS) refers to the maximum angle at which a vessel can heel (lean to one side) before it loses its ability to...

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  • General Nautical Terminology AntifoulPaint applied to hull below waterline to discourage dirt and wildlife attaching and slowing your progress. Has environmental implications
  • General Nautical Terminology, Navigation APEM... More Details
  • General Nautical Terminology Apparent WindThe wind we feel. If the true wind is hitting the boat on the beam or in front of the beam the apparent wind will be situated between the boat... More Details
  • General Nautical Terminology, Navigation Appraise, Plan, Execute, Monitor (APEM)... More Details
  • Organisation ASA

    A US-based organisation that provides sailing education, certification, and accreditation for sailing schools and instructors. 

    The American...

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  • General Nautical Terminology AshoreOn the land; or aground
  • General Nautical Terminology AsternThe area behind the stern (back) of the vessel
  • Nautical Saying At loggerheads

    At loggerheads is a nautical term referring to two ships positioned with their respective loggers (wooden blocks used for securing the ship's...

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  • Flag Semaphore Attention (Flag Semaphore)
    Error (Flag Semaphore) - Waving Both Flags

    This shape is used to gain the receiver's attention and is used at the beginning of a transmission. The message recipient responds with the...

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  • General Nautical Terminology Automatic Identification System (AIS)

    A maritime communication system that automatically transmits and receives vessel information such as position, speed, and course to enhance...

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  • General Nautical Terminology Autonomous Underwater Vehicle (AUV)

    An Autonomous Underwater Vehicle (AUV) is a self-propelled, unmanned underwater vehicle capable of operating independently without direct human...

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  • General Nautical Terminology AutopilotEquipment that allows the boat steer a course automatically using either compass bearing or a course relative to wind direction
  • General Nautical Terminology AUV

    An Autonomous Underwater Vehicle (AUV) is a self-propelled, unmanned underwater vehicle capable of operating independently without direct human...

    More Details
  • General Nautical Terminology AuxiliaryA term for a saying a boat that has auxiliary power, i.e. an engine
  • General Nautical Terminology AVS

    The Angle of Vanishing Stability (AVS) refers to the maximum angle at which a vessel can heel (lean to one side) before it loses its ability to...

    More Details
  • General Nautical Terminology AwashLevel with the surface of the water which just washes over an object
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