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      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.
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  • 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.
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Glossary

AJAX progress indicator

Marine navigation has its own secret language, and let’s face it—half of it sounds like someone making things up after too much grog. You’ve got your 'dead reckoning,' which isn’t nearly as ominous as it sounds, and 'bearing,' which has nothing to do with polar bears but everything to do with pointing the right way. Don’t even get us started on 'knots'—why measure speed like you’re tying a shoelace? And then there’s 'fix (not for your engine) and 'DR' (spoiler: it’s not a doctor). If you’re baffled, don’t worry—we’re here to help you decipher this nautical code so you can sound like a pro, not a landlubber who’s lost their compass.

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Results: 140
  • Term
    Definition
  • General Nautical Terminology, Navigation APEM More Details
  • General Nautical Terminology, Navigation Appraise, Plan, Execute, Monitor (APEM) More Details
  • General Nautical Terminology, Navigation Bearing

    The direction or angle between a reference point, typically true north, and an object or destination, usually expressed in degrees.

    A bearing...

    More Details
  • General Nautical Terminology, Navigation Bearing to Waypoint (BTW)

    The direction from a vessel's current position to a predetermined navigational point or waypoint.

    In marine navigation, Bearing to Waypoint is...

    More Details
  • General Nautical Terminology, Navigation BTW

    The direction from a vessel's current position to a predetermined navigational point or waypoint.

    In marine navigation, Bearing to Waypoint is...

    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...

    More Details
  • 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...

    More Details
  • General Nautical Terminology, Navigation Chart

    A detailed map used in marine navigation, showing water depths, hazards, and other critical information for safe passage.

    A marine chart...

    More Details
  • General Nautical Terminology, Navigation Chronometer

    A highly accurate timekeeping instrument, specifically designed for determining longitude at sea.

    A chronometer is a precision timepiece used...

    More Details
  • General Nautical Terminology, Navigation Closest Point of Approach (CPA)

    Used primarily in maritime and aviation contexts to describe the shortest distance that will be achieved between two moving objects, such as...

    More Details
  • General Nautical Terminology, Navigation Cocked Hat

    The small triangular area formed when three position lines on a nautical chart intersect but do not meet at a single point, indicating a degree...

    More Details
  • General Nautical Terminology, Navigation COG

    The actual path a vessel follows over the surface of the Earth, as opposed to its heading or intended course.

    Course Over Ground (COG) is a...

    More Details
  • Navigation Compass Add East for True (CADET)

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

    More Details
  • General Nautical Terminology, Navigation Compass Rose

    A circular diagram on nautical charts and compasses that displays directions relative to true north and magnetic north, often including...

    More Details
  • General Nautical Terminology, Navigation, Safety Constant Bearing, Decreasing Range (CBDR)

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

    More Details
  • General Nautical Terminology, Navigation Contour Line

    A line on a nautical chart that connects points of equal depth below the water's surface, representing the underwater topography.

    A contour...

    More Details
  • General Nautical Terminology, Navigation Coordinated Universal Time (UTC)

    The primary time standard by which the world regulates clocks and time serving as the basis for civil time globally.

    Coordinated Universal...

    More Details
  • General Nautical Terminology, Navigation, Weather (Meteorology) Coriolis Effect

    The apparent deflection of moving fluids, such as air or water, caused by the Earth's rotation, influencing large-scale ocean currents and wind...

    More Details
  • General Nautical Terminology, Navigation Course Over Ground (COG)

    The actual path a vessel follows over the surface of the Earth, as opposed to its heading or intended course.

    Course Over Ground (COG) is a...

    More Details
  • General Nautical Terminology, Navigation CPA

    Used primarily in maritime and aviation contexts to describe the shortest distance that will be achieved between two moving objects, such as...

    More Details
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