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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: 143
  • Term
    Definition
  • General Nautical Terminology, Weather (Meteorology) Southeast Iceland

    Sea area of the Met Office Shipping Forecast. Located southeast of Iceland in the North Atlantic.

    Southeast Iceland covers waters renamed from...

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  • General Nautical Terminology, Weather (Meteorology) South Utsire

    Sea area of the Met Office Shipping Forecast. Situated in the North Sea, south of Utsira Island off the west coast of Norway.

    Also named for...

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  • General Nautical Terminology Sou’westerA waterproof oilskin hat with a broad brim
  • Flag Semaphore Space (Flag Semaphore)
    Rest (Flag Semaphore)

    This shape indicates a space, usually between words. The same shape is also used for Rest (Flag Semaphore) & Ready (Flag Semaphore).

    More Details
  • General Nautical Terminology Spar

    Any long, sturdy pole or beam used on a ship to support sails, rigging, or other equipment. Spars are typically made of wood, metal, or composite...

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  • General Nautical Terminology Speed Made GoodThe speed made good over the ground; that is , the boat speed corrected for tidal stream and leeway
  • General Nautical Terminology, Navigation Speed Over Ground (SOG)

    The actual velocity of a vessel relative to the Earth's surface, accounting for the effects of currents, tides, and other environmental...

    More Details
  • General Nautical Terminology, Navigation Speed Through Water (STW)

    The velocity at which a vessel moves relative to the water it is travelling through, excluding the effects of current or tidal flow.

    Speed...

    More Details
  • General Nautical Terminology Spill WindTo ease the sheets so that the sail is only partly filled by the wind, the rest being spilt
  • General Nautical Terminology Spinnaker

    A large, lightweight, and often colourful sail designed for use when sailing downwind, typically set forward of the mainsail to maximise speed...

    More Details
  • General Nautical Terminology, Parts of a Boat Spinnaker Pole

    A spar used on sailing vessels to control one clew of a spinnaker sail when sailing downwind.

    A spinnaker pole is a key piece of equipment...

    More Details
  • General Nautical Terminology SpitA projecting shoal or strip of land connected to the shore
  • General Nautical Terminology Splice

    A method of joining two ropes or lines by interweaving their strands to form a strong, secure connection.

    A splice is a fundamental technique...

    More Details
  • General Nautical Terminology Sportbootführerschein (SBF)

    A German boating licence required for operating recreational motorboats and sailing vessels above certain power or length limits in German...

    More Details
  • General Nautical Terminology Sportbootführerschein Binnen (SBF Binnen)

    A German boating licence required for operating recreational motorboats and sailing vessels on inland waterways. 

    The Sportbootführerschein...

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  • General Nautical Terminology Sportbootführerschein See (SBF See)

    A German boating licence required for operating recreational motorboats and sailing vessels with an engine of more than 15 horsepower in coastal...

    More Details
  • General Nautical Terminology Sportküstenschifferschein (SKS)

    A German recreational boating licence required for operating yachts under sail or power in coastal waters up to 12 nautical miles...

    More Details
  • General Nautical Terminology Sports BoatSports boats are sailing vessels designed with one thought in mind - speed! There are many different classes (designs) of sports boats that often... More Details
  • General Nautical Terminology, Parts of a Boat Spray Hood

    A protective canvas or fabric structure, often supported by a metal frame, installed over the companionway of a boat to shield the cockpit and...

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

    Horizontal or angled spars attached to a yacht's mast, used to hold the shrouds away from the mast and improve the stability and tension of the...

    More Details
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