High Quality Content by WIKIPEDIA articles! A derrick is a lifting device composed of one mast or pole which is hinged freely at the bottom. It is controlled by lines (usually four of them) powered by some means such as man-hauling or motors, so that the pole can move in all four directions. A line runs up it and over its top with a hook on the end, like with a crane. It is commonly used in docks and onboard ships. Some large derricks are mounted on dedicated vessels, and are often known as "floating derricks". The device was named for its resemblance to a type of gallows from which a hangman's noose hangs. The derrick type of gallows in turn got its name from Thomas Derrick, an English executioner from the Elizabethan era.

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