2001: A Space Odyssey is a 1968 science fiction novel by Arthur C. Clarke. It was developed concurrently with Stanley Kubrick's film version and published after the release of the film. Clarke and Kubrick worked on the book together, but eventually only Clarke ended up as the official author. The story is based in part on various short stories by Clarke, most notably "The Sentinel" (written in 1948 for a BBC competition, but first published in 1951 under the title "Sentinel of Eternity"). By 1992, the novel had sold 3 million copies worldwide. For an elaboration of Clarke and Kubrick's collaborative work on this project, see The Lost Worlds of 2001, Arthur C. Clarke, Signet, 1972.
The first part of the novel (in which aliens influence the primitive human ancestors) is similar to the plot of an earlier Clarke story, "Encounter in the Dawn".