Diesel Engine A diesel engine is an internal combustion engine which operates using the diesel cycle (named after Dr. Rudolph Diesel). The defining feature of the diesel engine is the use of compression ignition to burn the fuel, which is injected into the combustion chamber during the final stage of compression. This is in contrast to a petrol (gasoline) engine, which uses the Otto cycle, in which a fuel/air mixture is ignited by a spark plug.

Yawl
A yawl (from Dutch Jol) is a two-masted sailing craft similar to a sloop or cutter but with an additional mizzen mast well aft of the main mast, often right on the transom. A small mizzen sail is hoisted on the mizzen mast.

The yawl was originally developed as a rig for commercial fishing boats, one good example of this being the Salcombe Yawl (a traditional small fishing boat built in Devon). In its heyday, the rig was particularly popular with single-handed sailors, such as circumnavigators Joshua Slocum and Francis Chichester. This was largely due to the remarkable ability of a yawl to be trimmed to follow a compass course accurately despite minor wind shifts. Modern self-steering and navigation aids have made this less important, and the yawl has generally fallen out of favor.

In the 1950s and 60s yawls were developed for ocean racing to take advantage the handicapping rule that did not penalize them for flying a mizzen staysail, which on long ocean races, often down wind, were a great advantage, the best example of this being Olin Stephens' Finisterre.

Passenger ship
Passenger ships include ferries, which are vessels for day or overnight short-sea trips moving passengers and vehicles (whether road or rail); ocean liners, which typically are passenger or passenger-cargo vessels transporting passengers and often cargo on longer line voyages; and cruise ships, which typically transport passengers on round-trips, in which the trip itself and the attractions of the ship and ports visited are the principal draw.
An ocean liner is the traditional form of passenger ship. Once such liners operated on scheduled line voyages to all inhabited parts of the world. With the advent of airliners transporting passengers and specialized cargo vessels hauling freight, line voyages have almost died out. But with their decline came an increase in sea trips for pleasure, and in the latter part of the 20th century ocean liners gave way to cruise ships as the predominant form of large passenger ship.
Although some ships have characteristics of both types, the design priorities of the two forms are different: ocean liners value speed and traditional luxury while cruise ships value amenities (swimming pools, theaters, ball rooms, casinos, sports facilities, etc.) rather than speed. These priorities produce different designs. In addition, ocean liners typically were built to cross the Atlantic Ocean between Europe and the United States or travel even further to South America or Asia while cruise ships typically serve shorter routes with more stops along coastlines or among various islands.
For a long time cruise ships were never as large as the old ocean liners had been, but in the 1980s this changed when Knut Kloster, the director of Norwegian Caribbean Lines, bought one of the biggest surviving liners, the SS France, and transformed her into a huge cruise ship, which he renamed the SS Norway. Her success demonstrated that there was a market for large cruise ships. Successive classes of ever-larger ships were ordered, until the Cunard liner Queen Elizabeth was finally dethroned from her 56-year reign as the largest passenger ship ever built.

Viking Ships
The European history is not only vast and interesting, but has been a major contributing factor to the developments of the world. The technological advances, cultural revolutions, continuous wars, devastating epidemics and gigantic empires have all played a part in what the world is today. The Viking civilization that dominated Northern Europe during 793 ? 1066 AD were known more for their naval prowess and raid attacks than anything else. The Vikings had a unique culture and traditions, and even though they were involved in large scale pillaging and warfare, they followed a high code of honor both in warfare and justice.

The Viking ships basically fall in three categories, large transport vessels (Knarr), Longships, for military use, and small coastal sailing and exploration vessels (Karv). Although as often depicted, all Viking ships did not carry the ?dragonhead? or ?serpent? figures. They were used mainly on warships or ships owned by high-ranked people. The Knarr were known for their maneuverability and loading capacity. The other designs included Byrdling, Skute and Ferje. The longships also had a number of variations, the Busse, the Skeide, the Snekke, the Sud, and Drakkar. The Busse were reportedly large capacity Viking ships with cargo capability, such as the "Ormen Lange" of King Olav Tryggvason, and they could have as many as 35 pair of oars. The Skeide was a Busse variation with smaller size and capacity. The Snekke were the most common ships, used by Canute the Great, and William the Conqueror, renowned for their speed and durability. The Suds evolved near the end of the Viking era and are said to be the biggest Longships. The Drakkar are the most easily recognizable Viking ships due to their distinct dragon or serpent design that symbolized the superior rank of the commanding warrior.

The basic characteristic of Viking ships can be summed up as having a single mast, exceptionally long parallel oars, and the clinker design used for construction, which involved overlapping thick wooden boards.

Tall Ships
Ships, and other sea vessels have been an integral part of human civilization since time immemorial. Shipbuilding as an art, was mastered by the British, and was the main reason why they continued to dominate the world for centuries. Colonial empires of other European countries such as Spain, France, Denmark and Portugal flourished as well, but they could never dominate the trade routes like the British navy. However, the USA has the biggest Navy in the world as of now, and it continues to expand in size and technology.

Tall ships are typically sailing vessels, that have a complex sail plan and are heavily rigged. They include the various modern schooners, brigantines, brigs and barques designs, which has fore-and-aft sails and may have two or three masts, with at least one being square rigged. They are easily recognized due to their characteristic tall mast and a number of sails. The best opportunity for sailing on tall ships in US is to approach the Tall Ships of Maine that take tourists for rides in summer. The American Sail Training Association can be contacted for volunteer work on tall ships or even for a vocational sea-training course. Their popularity has been recently increased by pirate movies and the attention and coverage given to the Tall Ship's Races (formerly known as the "Cutty Sark Tall Ships' Races").

The races are held in Europe every year and include participation from as many as 36 countries. These races feature the biggest tall ships in the world. It was first organized by a London lawyer in 1956, and was meant to be a farewell to the ships of that era. However, after taking into account the public interest generated, it was decided to form a Sail Training International Association that would promote such activities, especially amongst the youth of the world.

Wooden Ship Models
Wooden ship models are built-to-scale representations of modern or ancient sea-faring vessels.

Traditionally, all types of ship models have been built of wood, though with the advent of plastic and sheet metal, these have been used for amateur kits. Of course, wooden models project grandeur and finesse. The ancient Egyptians were the pioneers who made detailed ship models. The models were crafted as part of funeral rituals, which forced the builders to strive for precision, otherwise the unmitigated soul would pester them. The ship models kept inside the coffin were supposed to transport the soul of the deceased to the next world.

Modern-day sea-faring received much instruction from these carefully preserved, 5,000- year-old models. Specimens of these boats found a place in the British Museum, the Louvre, the Metropolitan Museum of Art, and many other museums worldwide.

Modern-day ship models came into existence before or during the construction of many eighteenth- and nineteenth-century warships. These were known as Admiralty or Shipyard models. Many of these models did not show the timbering they would have in the actual vessel, but the models illustrated the form of the hull and details of the deck furnishings, masts, spars, and general frame. The models provided the non-sea-faring financiers with a bird’s-eye view of the vessel that was to come into being. There are several types of construction of a wooden ship model. Some are carved from a single block of wood, others by gluing together blocks of wood, or by gluing together of slabs of wood into a laminated block. Others are built on what is called plank-on frame, built just as the full-size ship is constructed.

Wooden models of all types of vessels—luxury cruise liners, war ships, sailing ships—are available from dealers. A wooden model of a Chalutier ship costs $149.95; a USS Ronald Regan model costs $999; a wooden model Schooner costs $26.96; a Harvey wooden model costs $110; a Cutty Sark Wooden model costs $189; and an Atlantic costs $195.95. There are various price ranges for the connoisseur.