Although the novel and film were developed simultaneously,
the novel follows early drafts of the film, from which the final version of the film deviated. These changes were often for practical reasons relating to what could be filmed economically, and
a few were due to differences of opinion between Kubrick and Clarke. The most notable differences are a change in the destination planet from
Saturn to
Jupiter, and the nature of the sequence of events leading to HAL's demise. Stylistic differences may be more important than content differences. Of lesser importance are the appearance of the monolith, the age of HAL, and the novel giving names to various spacecraft, prehistoric apes, and HAL's inventor.