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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: 87
  • Term
    Definition
  • General Nautical Terminology, Parts of a Boat Cabin

    An enclosed space on a boat or ship that provides shelter and accommodation for passengers or crew.

    A cabin on a boat or ship is a designated...

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  • General Nautical Terminology Cable

    Unit of measure (distance)

    A cable is a unit of distance traditionally used to measure short distances at sea. It is generally considered...

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  • General Nautical Terminology Cable More Details
  • Navigation CADET

    The CADET mnemonic can help remember the corrections needed when converting between True North and Compass North bearings. It assists in...

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  • General Nautical Terminology, Signals & Communication Call Sign

    A unique identifier assigned to a vessel or maritime station for communication purposes, typically used in radio transmissions.

    A call sign is...

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  • General Nautical Terminology Cam Cleat

    A mechanical device with spring-loaded, opposing cams that grip a rope or line to hold it securely while allowing for quick adjustments. 

    A...

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  • Flag Semaphore, Signals & Communication Cancel--Disregard (Flag Semaphore)

    Cancel (or Disregard) informs the receiver to disregard the previous message or cancel the signalling. There is no specific attachment to...

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  • General Nautical Terminology CapsizeWhen a ship or boat overturns, exposing the keel or centre board
  • General Nautical Terminology Cardinal Bearing

    Cardinal Bearings are the main points on a compass, expressed by their name. There are four main cardinal points, North, South, East, and West...

    More Details
  • General Nautical Terminology Cardinal Mark

    Buoy or pillar placed North, East, South or West side of an obstruction to warn vessels away.

    Cardinal marks indicate that the deepest water...

    More Details
  • General Nautical Terminology Cast OffTo let go a rope or line
  • General Nautical Terminology, Parts of a Boat Catamaran

    A type of multihulled vessel featuring two parallel hulls of equal size, connected by a deck or framework, offering stability, speed, and...

    More Details
  • Abbreviation, General Nautical Terminology CBD

    A vessel whose ability to deviate from its current course is significantly restricted due to the depth of water relative to its draught.

    A...

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  • General Nautical Terminology, Navigation, Safety CBDR

    A navigational situation where two vessels maintain the same relative bearing to each other while the distance between them diminishes, often...

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  • Flag / Pennant, Signals & Communication Code Flag Charlie (C)

    The International Maritime Signal Flag Charlie.

    Meaning

    Affirmative.
    If appended with a Numeral Pennant, a Magnetic Bearing.

  • Courses, RYA CEVNI test onlineThe CEVNI Test Online is a certification required for those navigating inland waterways in Europe. The test covers the European Code for Inland... More Details
  • General Nautical Terminology Chafing

    Chafing is damage or wear caused by friction between two surfaces, such as ropes rubbing against a boat's railing or sails rubbing against a...

    More Details
  • General Nautical Terminology Chainplate

    A strong metal plate, usually stainless steel, bolted to a boat’s hull or deck to which the shrouds or stays of the rigging are...

    More Details
  • General Nautical Terminology Chandler

    A supplier or dealer specialising in providing equipment, provisions, and supplies for ships and their crews.

    A chandler refers to a...

    More Details
  • General Nautical Terminology Channel

    A navigable waterway, often a natural or dredged passage, that allows vessels to travel between larger bodies of water or through shallow...

    More Details
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