- published: 25 Mar 2013
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In politics, the Left, left-wing and leftists are people or views which generally support social change to create a more egalitarian society. They usually involve a concern for those in society who are disadvantaged relative to others and an assumption that there are unjustified inequalities (which right-wing politics views as natural or traditional) that should be reduced or abolished.
The political terms Left and Right were coined during the French Revolution (1789-1799), referring to the seating arrangement in the Estates General: those who sat on the left generally supported the radical changes of the revolution, including the creation of a republic and secularization, while those on the right were supportive of the traditional institutions of the Old Regime. Use of the term "Left" became more prominent after the restoration of the French monarchy in 1815 when it was applied to the "Independents". The term was later applied to a number of revolutionary movements, especially socialism, anarchism and communism as well as more reformist movements such as social democracy and social liberalism.
A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid. A wing is an airfoil, which has a streamlined cross-sectional shape producing a useful lift to drag ratio.
The word "wing" from the Old Norse vængr for many centuries referred mainly to the foremost limbs of birds (in addition to the architectural aisle.) But in recent centuries the word's meaning has extended to include lift producing appendages of insects, bats, pterosaurs, boomerangs, some sail boats and aircraft.
"Wing" can also mean an inverted airfoil on a race car that generates a downward force to increase traction.
Various species of penguins and other flighted or flightless water birds such as auks, cormorants, guillemots, shearwaters, eider and scoter ducks and diving petrels are avid swimmers, and use their wings to propel through water.
A wing's aerodynamic quality is expressed as its lift-to-drag ratio. The lift a wing generates at a given speed and angle of attack can be one to two orders of magnitude greater than the total drag on the wing. A high lift-to-drag ratio requires a significantly smaller thrust to propel the wings through the air at sufficient lift.