The second oldest simple machine was the inclined plane (ramp), which has been used since prehistoric times to move heavy objects. The hand axe is the first example of a wedge, the oldest of the six classic simple machines, from which most machines are based. The hand axe, made by chipping flint to form a wedge, in the hands of a human transforms force and movement of the tool into a transverse splitting forces and movement of the workpiece. The word engine used as a (near-) synonym both by Harris and in later language derives ultimately (via Old French) from Latin ingenium 'ingenuity, an invention'. Compound Machines, or Engines, are innumerable. the Ballance, Leaver, Pulley, Wheel, Wedge, and Screw. Simple Machines are commonly reckoned to be Six in Number, viz. Machine, or Engine, in Mechanicks, is whatsoever hath Force sufficient either to raise or stop the Motion of a Body. The OED traces the formal, modern meaning to John Harris' Lexicon Technicum (1704), which has: The modern meaning develops out of specialized application of the term to stage engines used in theater and to military siege engines, both in the late 16th and early 17th centuries. In the 17th century, the word machine could also mean a scheme or plot, a meaning now expressed by the derived machination. This meaning is found in late medieval French, and is adopted from the French into English in the mid-16th century. A wider meaning of 'fabric, structure' is found in classical Latin, but not in Greek usage. The word mechanical (Greek: μηχανικός) comes from the same Greek roots. The English word machine comes through Middle French from Latin machina, which in turn derives from the Greek ( Doric μαχανά makhana, Ionic μηχανή mekhane 'contrivance, machine, engine', a derivation from μῆχος mekhos 'means, expedient, remedy' ). Examples include: a wide range of vehicles, such as trains, automobiles, boats and airplanes appliances in the home and office, including computers, building air handling and water handling systems as well as farm machinery, machine tools and factory automation systems and robots. Modern machines are complex systems that consist of structural elements, mechanisms and control components and include interfaces for convenient use. Renaissance natural philosophers identified six simple machines which were the elementary devices that put a load into motion, and calculated the ratio of output force to input force, known today as mechanical advantage.
They can also include computers and sensors that monitor performance and plan movement, often called mechanical systems. Machines can be driven by animals and people, by natural forces such as wind and water, and by chemical, thermal, or electrical power, and include a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement.
The term is commonly applied to artificial devices, such as those employing engines or motors, but also to natural biological macromolecules, such as molecular machines. A machine is a physical system using power to apply forces and control movement to perform an action.
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