Clifford D. Simak, American journalist and author (d. 1988)

Clifford Donald Simak (; August 3, 1904 – April 25, 1988) was an American science fiction writer. He won three Hugo Awards and one Nebula Award. The Science Fiction Writers of America made him its third SFWA Grand Master, and the Horror Writers Association made him one of three inaugural winners of the Bram Stoker Award for Lifetime Achievement.