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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: 1071
  • Term
    Definition
  • General Nautical Terminology ODAS

    The Ocean Data Acquisition System (ODAS) is a system used to collect, process, and transmit various types of oceanographic data. This system...

    More Details
  • General Nautical Terminology Officer of the Watch (OOW)

    The designated officer responsible for the safe navigation and operation of a vessel during their assigned watch period. 

    The Officer of the...

    More Details
  • General Nautical Terminology OffshoreWind blowing away from the land or “being at sea”
  • Courses, RYA Offshore Personal Survival (RYA/World Sailing)The Offshore Personal Survival course is an intensive program designed for sailors participating in offshore and ocean races. Participants learn... More Details
  • General Nautical Terminology OilskinsWaterproof clothing worn in foul weather
  • Flag Semaphore, Signals & Communication Letter O (Flag Semaphore)
    Flag semaphore indicating the letter O.

    Flag semaphore indicating the letter O.

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

    International Morse Code sequence representing the letter O.

  • General Nautical Terminology OnshoreWind blowing towards the land or “not at sea”.
  • General Nautical Terminology On the Port BowAhead of a vessel at an angle to the bows, but forward of the beam, to the left
  • General Nautical Terminology On the Port QuarterAt an angle to the stern of your vessel, but abaft the beam, to the left
  • General Nautical Terminology On the Starboard BowAhead of a vessel at an angle to the bows, but forward of the beam, to the right
  • General Nautical Terminology On the Starboard QuarterAt an angle to the stern of your vessel, but abaft the beam, to the right
  • General Nautical Terminology OOW

    The designated officer responsible for the safe navigation and operation of a vessel during their assigned watch period. 

    The Officer of the...

    More Details
  • Phonetic Alphabet, Signals & Communication Oscar

    Pronounced: OSS-cah

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

  • General Nautical Terminology OuthaulA line with which the mainsail is hauled out along the boom
  • General Nautical Terminology OverfallsTurbulent waters where is a sudden change in depth or where two tidal streams meet
  • General Nautical Terminology Overhand loop

    A loop that crosses on top of the standing part of a rope when tying a knot.

  • General Nautical Terminology PainterThe line at the bow of a dinghy
  • General Nautical Terminology, Safety, Signals & Communication Pan Pan

    An internationally recognised maritime urgency signal used in radio communications to indicate a situation that is urgent but does not pose an...

    More Details
  • Phonetic Alphabet, Signals & Communication Papa

    Pronounced: pah-pah

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

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