Holograms
Holograms in Red Dwarf are visual projections of dead people, with the person's personality, knowledge and experience, like living humans they have free will and can learn from experience. Holograms are apparently commonplace on 22nd century earth, for example, the newsreader on Channel 27 is a hologram. Holly is only capable of sustaining one hologram aboard the ship, due to the fact that the amount of energy required to power a hologram for one second could 'power the whole of Paris for three years', and for the majority of the series, that hologram is Arnold Rimmer. However, in Confidence and Paranoia, Lister's Confidence reveals that, if all non-essential electrical equipment is switched off, then two holograms can be run at once. The technology is improved as the series progresses, with the introduction of a "light-bee", which the physical generator of the hologram remotely. The light-bee is also upgraded in Legion to "hard light" allowing Rimmer a near-indestructible physical presence.
One notable group of holograms is those on the Holoship Enlightenment, who take the cream of Space Corps officers to travel the universe. As the entire ship is holographic, all the holograms on board effectively have a physical presence.
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