This article’s quite good. It even has some numbers to back up my bland assertions.
What do the terms ‘left wing’ and ‘right wing’ mean? Well, if you are the BBC, ‘left wing’ is a term used mainly in sport. Insofar as it is used in politics, it is used to describe the mainstream. ‘Right wing’, by contrast, is a term used to describe political fringe groups: racist, violent, and illegal groups.
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The phrase ‘right wing’ is often accompanied by words such as ‘extremist’ or qualifiers such as ‘far right’. For example, the search ‘far right’ produces 142 pages while ‘far left’ only 54. ‘Right wing’ and ‘extreme’ generates 29 pages while ‘left wing’ and ‘extreme’ just 18. This is because the BBC links the term ‘right wing’ with the BNP and National Front, while the search for ‘left wing’ does not produce any early matches linking to stories about the Socialist Workers’ Party, Revolutionary Communist Party, or even Respect, a party which won a seat at the last general election, and which is dominated by the SWP.