"The alt-right, or alternative right, is a loosely defined group of people with far-right ideologies who reject mainstream conservatism in favor of white nationalism, principally in the United States, but also to a lesser degree in Canada and Europe.
Alt-right beliefs have been described as isolationist, protectionist, antisemitic, and white supremacist, frequently overlapping with Neo-Nazism, nativism and Islamophobia, antifeminism and homophobia, right-wing populism, and the neoreactionary movement. The concept has further been associated with multiple groups from American nationalists, neo-monarchists, men's rights advocates, and the 2016 presidential campaign of Donald Trump.
The alt-right has its roots on Internet websites such as 4chan and 8chan, where anonymous members create and use Internet memes to express their ideologies."
Source:Wikipedia
"Alt-left is a neologism begun by conservative online media in 2016 suggesting the existence of a similar ideological fringe movement to the Alt-right on the political left. The term began being used by Sean Hannity and Fox News to described groups or outlets or individuals who were perceived as being critical of President-elect Donald Trump. Scholars note that there is no equivalent to the alt-right on the political left. The term gained popularity when it was used against Bernie Sanders and Elizabeth Warren. The term and the concept of an "alt-left" as an opposite-but-equal mirror of the alt-right have been severely criticized. The term gained prevalence when U.S. president Donald Trump used the phrase during remarks on the Charlottesville rally on August 15, 2017.
The usage of the term is made in contradictory ways, with scholars noting that there is no equivalent to the alt-right on the hard and far political left.
Unlike the term "alt-right" (which was coined by those on the extreme right who comprise the movement), as noted by Washington Post writer Aaron Blake, "alt-left" was "coined by its opponents and doesn't actually have any subscribers". According to George Hawley, an assistant professor of political science at the University of Alabama, no such label has been adopted by any members of the progressive left"
Source: Wikipedia
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