Libertarianism (Latin: liber, “free”) is a set of related political philosophies that uphold liberty as the highest political end. This includes emphasis on the primacy of individual liberty,political freedom, and voluntary association. It is the antonym to authoritarianism. Different schools of libertarianism disagree over whether the state should exist and, if so, to what extent. While minarchists propose a state limited in scope to preventing aggression, theft, breach of contract and fraud, anarchists advocate its complete elimination as a political system. While certain libertarian currents are supportive of laissez-faire capitalism and private property rights, such as in land and natural resources, others reject capitalism and private ownership of the means of production, instead advocating their common or cooperative ownership and management. 
In the Stanford Encyclopedia of Philosophy, libertarianism is defined as the moral view that agents initially fully own themselves and have certain moral powers to acquire property rights in external things. Libertarian philosopher Roderick Long defines libertarianism as “any political position that advocates a radical redistribution of power from the coercive state to voluntary associations of free individuals”, whether “voluntary association” takes the form of the free market or of communal co-operatives.In the United States, the term libertarianism is often used as a synonym for economic liberalism.
Many countries throughout the world have libertarian parties (see list of libertarian political parties).
The term libertarian in a metaphysical or philosophical sense was first used by late-Enlightenment free-thinkers to refer to those who believed in free will, as opposed to incompatibilist determinism. The first recorded use was in 1789 by William Belsham in a discussion of free will and in opposition to “necessitarian” (or determinist) views.
Libertarian as an advocate or defender of liberty especially in the political and social spheres was used in 1796 in London Packet on the 12th of February:
Lately marched out of the Prison at Bristol, 450 of the French Libertarians.
The word libertarian was used also in a political sense in 1802, in a short piece critiquing a poem by “the author of Gebir”:
The author’s Latin verses, which are rather more intelligible than his English, mark him for a furious Libertarian (if we may coin such a term) and a zealous admirer of France, and her liberty, under Bonaparte; such liberty!
The use of the word “libertarian” to describe a new set of political positions has been tracked to the French cognate, libertaire, which was coined in 1857 by French anarchist Joseph Djacque who used the term to distinguish his libertarian communist approach from the mutualism advocated by Pierre-Joseph Proudhon. By 1878, Sir John Seeley could characterize a person “who can properly be said to defend liberty” (by opposing tyranny or “resist[ing] the established government”) as a “libertarian.”Libertarian has been used by some as a synonym for anarchism since the 1890s. By 1901, Frederic William Maitland could use the term to capture a cultural attitude of support for freedom. Observing that “the picture of an editor defending his proof sheets [...] before an official board of critics is not to our liking,” Maitland emphasized that “[i]n such matters Englishmen are individualists and libertarians.” As early as 1923, H. L. Mencken could write: “My literary theory, like my politics, is based chiefly upon one idea, to wit, the idea of freedom. I am, in belief, a libertarian of the most extreme variety.”Albert Jay Nock and Mencken were the first prominent figures in the US to call themselves “libertarians,” which they used to signify their allegiance to individualism and limited government, feeling that Franklin D. Roosevelt had co-opted the word “liberal” for his New Deal policies, which they opposed.
In the United States, where the meaning of liberalism has parted significantly from classical liberalism, classical liberalism has largely been renamed libertarianism and is associated with “economically conservative” and “socially liberal” political views (going by the common meanings of “conservative” and “liberal” in the United States), along with a foreign policy of non-interventionism.
Libertarianism – Wikipedia, the free encyclopedia