An oar is a tool used for marine propulsion. Oars have a flat blade at one end. The oarsmen grasp the oar at the other end. What distinguishes oars from paddles is that paddles are held by the paddler, and are not connected with the vessel. Oars generally are fastened to the vessel.

Oarsmen generally face the stern of the vessel, reach as far as they can towards the stern, insert the blade of their oar in the water. As they lean back, towards the vessel's bow, the blade of their oars sweeps the water towards the stern, providing forward thrust - see lever.

For thousands of years vessels were powered either by sails, or the mechanical work of oarsmen, or paddlers. Some ancient vessels were propelled by either oars or sail, depending on the speed and direction of the wind.

Oars used for transportation

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The oars used for transportation come in a variety of sizes. The oars used in small dinghies or rafts can be less than 2 metres long. In classical times warships were propelled by very long oars that might have several oarsmen per oar. These oars could be more than a dozen metres long.

Oars used for competitive rowing

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The oars used in competitive rowing are long (250–300 cm) poles with one flat end about 50 cm long and 25 cm wide, called the blade. The part of the oar the oarsman holds while rowing is called the Handle#Noun. While rowing, the oars are supported by metal frames attached to the side of the boat called outriggers. Classic oars were made out of wood, but modern oars are made from synthetic material, the most common being carbon fiber.

Oars used as trophies

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The sport of competitive rowing has developed a peculiar tradition of using an oar as a memento of significant race wins. A 'trophy oar' is not presented at the end of the race as a more familiar precious metal cup might be, but rather given by the club, school or university that the winning crew or rower represented.

A trophy oar is a competition oar that has been painted in the club colours and has then had the details of the race signwritten on the face of the blade. The most common format would have the coat of arms or crest of the club or school positioned in the centre, with the crew names and the race details arranged around this.

Many older universities (Oxford and Cambridge would be prime examples) and their colleges have long histories of using the trophy oar and many examples are on display in club houses around the world.

Sporting goods | Rowing | Marine propulsion

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