The character of Sheldon Cooper was inspired by a computer programmer personally known to series co-creator Bill Prady. He is named in honor of actor / producer Sheldon Leonard and Nobel Prize Laureate Leon Cooper. Chuck Lorre originally intended Johnny Galecki to play the role, but Galecki thought he would be "better suited '' for the character of Leonard. Lorre said that when Jim Parsons auditioned for the role, he was "so startlingly good '' that he was asked to reaudition "to make sure he had n't gotten lucky ''. Sheldon is one of four characters to appear in every episode of the series, along with Leonard, Howard, and Raj.
who is the character sheldon cooper based on
a computer programmer personally known to series co-creator Bill Prady