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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
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Glossary Archive

International Maritime Conventions

Legally binding agreements established by global maritime organisations to standardise regulations and ensure international shipping safety, security, and environmental protection. International Maritime Conventions are primarily developed and adopted by the International Maritime Organization (IMO), a specialised agency of the United Nations regulating shipping. These conventions are designed to create a uniform framework that governs various...


International Maritime Organisation

A specialised agency of the United Nations headquartered in London and responsible for regulating shipping, the IMO has 175 Member States. The IMO is responsible for improving the safety and security of international shipping and preventing pollution from ships. It is also involved in legal matters, including liability and compensation issues and the facilitation of...


International Maritime Signal Flags

A system of flags ships use to communicate messages, signals, or important information visually. Flags often represent letters, numbers, or specific meanings. International maritime signal flags are a standardised set of flags used globally in the marine industry to facilitate communication between vessels, ships, and shore stations. Each flag represents a letter of the alphabet,...


International Meridian Conference

A diplomatic meeting held in 1884 in Washington, D.C., where representatives from 25 nations convened to establish a standard prime meridian for global navigation and timekeeping. The International Meridian Conference was a pivotal event in maritime history, addressing the need for a unified system of longitudinal reference to aid in navigation and time standardisation. Prior...


International Morse Code

A standardised system of encoding text characters as sequences of dots (short signals) and dashes (long signals) used for communication, particularly in maritime and radio transmissions. International Morse Code is a globally recognised communication system that translates letters, numbers, and punctuation into a series of short and long signals, commonly referred to as "dots" and...


International Radiotelegraph Conference

A series of meetings establishing global standards and regulations for using radiotelegraphy, particularly in maritime communication. The International Radiotelegraph Conference was a pivotal event in the history of maritime communication, bringing together representatives from various nations to create a unified framework for the use of radio frequencies, particularly in maritime contexts. These conferences were held...


International Regulations for Preventing Collisions at Sea



International Telecommunication Union

A specialised agency of the United Nations responsible for coordinating global telecommunication operations and services, including radio frequency allocation and satellite orbits. The International Telecommunication Union (ITU) is critical in global communications, particularly in the maritime sector. Established in 1865, the ITU is one of the oldest international organisations and has evolved to address the...


IRC

A series of meetings establishing global standards and regulations for using radiotelegraphy, particularly in maritime communication. The International Radiotelegraph Conference was a pivotal event in the history of maritime communication, bringing together representatives from various nations to create a unified framework for the use of radio frequencies, particularly in maritime contexts. These conferences were held...


Irish Sea

Sea area of the Met Office Shipping Forecast. Covers the Irish Sea between Ireland and Great Britain. Between Ireland and Great Britain, the Irish Sea funnels Atlantic lows with frequent gales and severe storm surges. The Royal Charter Gale of October 1859 struck here with record gusts and over 800 fatalities on crowded passenger ships.


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