George Carlin, who died on 22 June, 2008, was one of the heroes of American stand-up comedy.

Taking his place in a lineage that includes Richard Pryor , Lenny Bruce and Bill Hicks , he was an outspoken exponent of explosive material with a marked leftist streak.

His style was borne out of 1960s counter culture and he cut the figure of an irate hippy on stage, with lank hair, untamed beard and a slovenly approach to dress.

But it was his irreverent routines that attracted the most controversy, even so far as landing him in front of the Supreme Court when his ‘Seven Dirty Words’ act – based around a list of words you couldn’t say on the radio that was, inevitably, broadcast on the radio in 1973 – was ruled to be indecent.

Mr Carlin, who was born on 12 May, 1937, in Manhattan, first came to prominence as a television comic in the ’60s, performing skits on The Ed Sullivan Show. He also stood in for Johnny Carson as a host of The Tonight Show.

He was arrested several times – one time with his mentor Lenny Bruce – for various acts of anti-establishment behaviour, from violating obscenity laws to refusing to carry identification.

He continued to challenge the powers that be into his old age, tackling the subject of ‘American Bullshit’ in his latest stand up show. He also appeared in several comedy films, including playing the sage Rufus in the Bill & Ted films (1989-91) and Cardinal Glick in Dogma (1999).