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Nautical Know How
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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 & 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.
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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 nauctical, including marinas u0026 training centres. If it exists, we’ve got it listed!
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      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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Glossary Archive

Hoist

To raise an object vertically, commonly a sail or flag, using a halyard. It typically uses a system of ropes, cables, pulleys, and sometimes a winch or hydraulic mechanism to facilitate lifting.


Holding Tank

A sealed onboard container designed to temporarily store wastewater, such as sewage or greywater, until it can be properly discharged at a designated facility. A holding tank is an essential component of a vessel's waste management system, particularly on boats equipped with toilets (marine heads) or sinks. Its primary purpose is to collect and store...


Horizontal Dilution of Precision

Used in satellite navigation and positioning systems to quantify the accuracy of horizontal position measurements. It is a unitless factor that indicates the geometric quality of the satellite configuration in relation to the receiver's position. A lower HDOP value indicates a more accurate horizontal position, while a higher HDOP value indicates a less accurate position...


Horseshoe Lifebuoy

A U-shaped flotation device designed to be thrown to a person overboard to provide buoyancy and aid in rescue. The horseshoe lifebuoy, also known as a horseshoe ring or horseshoe buoy, is a critical piece of safety equipment commonly found on recreational and commercial vessels. Its distinctive U-shape allows it to fit snugly around the...


Hotel

Pronounced: hoh-TELL The term for the letter H in the NATO Phonetic Alphabet.


Hounds

Attachments of stays to masts.


House flag

Any personal flag or club flag flown from starboard spreaders or flagstaff.


Hull

The watertight body or shell of a boat or ship, excluding the deck, rigging, and other superstructures. The hull is the fundamental structure of any vessel, designed to provide buoyancy and stability while keeping the water out. It is the part of the boat that makes contact with the water, and its shape and construction...


Hull Speed

The maximum efficient speed of a displacement-hulled vessel.


Hurricane Force

Beaufort Scale - Force 12 (Hurricane Force 12) Hurricane-force is a term used to describe wind speeds equal to or greater than 64 knots (74 miles or 119 kilometres per hour), the minimum wind speed threshold for a storm to be classified as a hurricane. Winds of this magnitude are capable of causing significant damage...


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