2001: A Space Odyssey has the distinction of being one of only a few classic books to be based on a movie, rather than the other way around. Its author, Arthur C. Clarke, based the novel on a screenplay he wrote in conjunction with Stanley Kubrick in 1964. The book, which was released a few months after the movie, fills in many details left unsettled in the movie.
2001 was written at the very beginning of the space age, before man first set foot on the moon in 1969. It was clearly inspired by much of the fascination with space, which gripped a nation exploring an uncharted terrain in the 1960s.
The 1960s were also a time of confrontation with the communist U.S.S.R. and tension over the potential for use of nuclear weapons. The Cuban Missile Crisis was recent history at the time 2001 was in the process of being conceived. The instability of foreign relations as well as the proliferation of nuclear weapons led many at the time to wonder whether a nuclear holocaust might be around the corner.
HAL is HAL 9000, not HAL 2001 as mentioned in the Themes, Motifs and Symbols section