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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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      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.

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        Find anywhere nautical, including marinas & training centres. If it exists, we’ve got it listed!
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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

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: 50
  • Term
    Definition
  • General Nautical Terminology, Weather (Meteorology) Land Breeze

    A local wind that blows from the land towards the sea, typically during the night, caused by the differential cooling rates of land and...

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  • General Nautical Terminology Landfall

    The event of a vessel sighting or reaching land after a voyage at sea.

    Landfall is a term used in the maritime world to describe the moment...

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  • General Nautical Terminology LanyardA short length of line used to secure an object such as a knife
  • General Nautical Terminology Lash DownTo secure firmly with a rope or line
  • General Nautical Terminology, Navigation LAT

    The lowest level that sea tides can reach under normal meteorological conditions, based on astronomical influences such as the gravitational pull...

    More Details
  • General Nautical Terminology Lateral MarkBuoy, or post used to mark Port and Starboard sides of a channel
  • General Nautical Terminology, Navigation Latitude

    The angular distance of a location on Earth's surface, measured in degrees(°), minutes('), and seconds('') north or south of the equator which is...

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  • General Nautical Terminology Lazarette

    A storage compartment located in the stern (aft) of a boat, typically used for stowing gear, equipment, or provisions.

    A lazarette is a...

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  • General Nautical Terminology Lazy JacksA network of cordage rigged to a point on the mast and to a series of points on either side of the boom that cradles and guides the sail onto the... More Details
  • Flag / Pennant, Signals & Communication Code Flag Lima (L)

    The International Maritime Signal Flag Lima.

    Meaning

    Stop immediately.
    If appended by a Numeral Pennant, Latitude (the first 2 digits...

    More Details
  • General Nautical Terminology Leading LightsLights positioned to assist entry into harbour or safe passage through a channel. Usually one light above another marks the correct course.
  • General Nautical Terminology LeadlineAn instrument used in navigation to measure water depth; a line attached to some lead. Usually the line is marked with knots at regular intervals.
  • General Nautical Terminology LeagueA unit of length, normally equal to three nautical miles.
  • Courses, RYA Learn to WingsurfThe RYA Learn to Wingsurf course introduces participants to the basics of wingsurfing. Participants learn how to control the wing, balance on the... More Details
  • General Nautical Terminology LeeThe direction towards which the wind blow
  • General Nautical Terminology LeechThe trailing edge of a triangular sail
  • General Nautical Terminology Lee-oh!Command given by helm when tacking as the bow passes through the wind. Tells the crew to reset the sails on the new course.
  • General Nautical Terminology, Weather (Meteorology) Leeshore

    A shoreline that lies downwind of a vessel, posing a potential hazard as the wind pushes the vessel towards it.

    A leeshore is a concept in...

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  • General Nautical Terminology Leeward

    The side of a vessel or an object that is sheltered from the wind, opposite to the windward side.

    Leeward is a crucial concept for...

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  • Flag Semaphore, Signals & Communication Letters to Follow (Flag Semaphore)

    This flag semaphore signal indicates a change from numbers to letters (Letters to follow). This switches back from numbers to the default...

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  • Courses, RYA Level 1 Start Powerboating (PB1)The RYA Level 1 Start Powerboating course introduces beginners to the basics of powerboat handling. Participants learn low-speed maneuvers, safety... More Details
  • Courses, RYA Level 2 Powerboat Handling (PB2)The RYA Level 2 Powerboat Handling course is a comprehensive two-day program that teaches participants the skills needed to operate powerboats... More Details
  • General Nautical Terminology, Safety Life Jacket

    A buoyant, wearable safety device designed to keep a person afloat in the water and reduce the risk of drowning. 

    A life jacket, also known as...

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  • General Nautical Terminology LifelinePersonal safety device attached to harness on lifejacket and to vessel strongpoint. Designed to keep you on board
  • General Nautical Terminology, Safety Liferaft

    An inflatable or rigid floating device designed to provide emergency refuge and safety for individuals forced to abandon a vessel at sea.

    A...

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  • General Nautical Terminology Lighthouse

    A tall, often cylindrical structure equipped with a powerful light and other navigational aids, built near coastlines or on islands to guide...

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  • Phonetic Alphabet, Signals & Communication Lima

    Pronounced: LEE-mah

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

  • General Nautical Terminology Line

    A rope used on a boat for various purposes, such as securing the vessel to a mooring (mooring line), adjusting sails (halyard or sheet), towing...

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  • General Nautical Terminology, Navigation Lines of Position (LOP)

    Navigational lines drawn on a chart, each representing a possible location of a vessel based on a single observation or measurement. 

    A line...

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  • General Nautical Terminology ListA permanent lean to one side or the other
  • General Nautical Terminology Listing

    The condition of a vessel leaning to one side due to an imbalance in weight or external forces. 

    A vessel lists when it tilts to port or...

    More Details
  • Flag Semaphore, Signals & Communication Letter L (Flag Semaphore)
    Letter L (Flag Semaphore)

    Flag semaphore indicating the letter L.

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

    International Morse Code sequence representing the letter L.

  • General Nautical Terminology LNM

    A Local Notice to Mariners (LNM) is a publication issued by maritime authorities to provide important information to mariners about navigational...

    More Details
  • General Nautical Terminology Local Notice to Mariners (LNM)

    A Local Notice to Mariners (LNM) is a publication issued by maritime authorities to provide important information to mariners about navigational...

    More Details
  • General Nautical Terminology Lock

    A gated section of a waterway, such as a canal or river, designed to raise or lower vessels between stretches of water at different levels.

    A...

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  • General Nautical Terminology, Parts of a Boat Locker

    A storage compartment or enclosed space on a boat, typically used for stowing equipment, gear, or provisions securely.

    A locker on a boat is a...

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  • General Nautical Terminology Logbook

    An official record maintained aboard a vessel that documents the ship's daily activities, including navigational data, weather conditions, and...

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  • General Nautical Terminology Log Line

    A device used historically by mariners to measure a vessel's speed through the water.

    The log line consists of a wooden board, known as the...

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  • General Nautical Terminology Log ReadingThe reading of distance travelled through the water usually taken every hour from the log and recorded in the deck log
  • General Nautical Terminology, Navigation Longitude

    The geographic coordinate that specifies the east-west position of a point on the Earth's surface, measured in degrees(°), minutes(') and...

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  • General Nautical Terminology, Safety Look-out

    A crew member assigned to maintain a continuous watch for potential hazards, other vessels, or navigational markers while at sea.

    A look-out...

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  • General Nautical Terminology, Navigation LOP

    Navigational lines drawn on a chart, each representing a possible location of a vessel based on a single observation or measurement. 

    A line...

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  • General Nautical Terminology Lose WayA vessel loses way when she slows down and stops in the water
  • General Nautical Terminology, Navigation Lowest Astronomical Tide (LAT)

    The lowest level that sea tides can reach under normal meteorological conditions, based on astronomical influences such as the gravitational pull...

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  • General Nautical Terminology Lubber LineThe marker in the compass which is aligned with the fore-and-aft line of the boat against which the course can be read off on the compass card
  • General Nautical Terminology Luff

    The leading edge, which is the part of the sail that faces the wind when the sail is set correctly.

    The luff of a sail is a critical part of...

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  • General Nautical Terminology Luff Up

    To steer a sailing vessel closer to the wind, reducing the angle between the boat's heading and the direction of the wind. 

    "Luff up" is a...

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  • General Nautical Terminology LullA temporary drop in wind speed
  • General Nautical Terminology, Weather (Meteorology) Lundy

    Sea area of the Met Office Shipping Forecast. Lies in the Bristol Channel, around Lundy Island off southwest England.

    Named for Lundy Island...

    More Details

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