He was born in DC and raised by a Catholic father and Jewish mother. His name is Szekely so resorted to the initials which sound like his Hungarian name.
C.K. wrote for a number of TV shows including Letterman, Conan O'Brien, Dana Carvey, and Chris Rock. He got 3 nominations for his work on Chris Rocks' show. He won the 1999 Best Writing in a Variety or Comedy Series.