Hab is the main computer of the ship named both as the Psion IV and Melissa V in Dave Hollins: Space Cadet, a recurring radio sketch on the Grant Naylor radio show Son of Cliché. These sketches were the prototypes for what would become Red Dwarf. Hab is the prototype for Holly and thus is similarly senile; some of Hab's dialogue later appears spoken by Holly in Red Dwarf. He is made to sound more computer-ish than Holly was, giving Hab a high pitched electronic tone. Hab was voiced by Chris Barrie, who would later play Arnold Rimmer in Red Dwarf. His name is presumably derived from HAL 9000 in Arthur C. Clarke's "2001: A Space Odyssey".