Simon has been revered as one of American Theatre's most classic comedic writers. He's won more Oscars and Tony's combined than any other writer which puts him in the running as one of the most successful writers in American pop culture history.
He began his career in 1950 writing alongside other notable comedic writers including Woody Allen and Mel Brooks for Sid Ceaser's live comedy show Your Show of Shows (See PBS' "American Masters" http://to.pbs.org/14qtbxu)
Since then he's written notable comedic classics including
Lost in Yonkers (1991) The Odd Couple (1968), Barefoot in the Park (1967) and Sweet Charity (1966).
His comedy is representative of an era in comedy that we don't often see replicated anymore. The jokes are calculated and familiar, they comment on complexities of American identity and they can be extracted from the text without much harm to the narrative. Simon's comedy is formulaic and it acts as a template for a lot of modern comedy that we see today.
Simon also wrote a lot of plays that worked within the context of his own personal history. His characters were often Jewish and from New York, just like Simon. His familiarity with these characters allowed his humour to be grounded in realism thereby riddling each piece with little nuances that grounded them in authenticity.
Sweet Charity closed its most recent New York run last fall. Read the New York Times review here: http://nyti.ms/T5Iadv