"a tiny ribbon of ticker tape"
mini computer
Creative Commons Attribution Share Alikemini computer - Credit: Toresbe

Early mini-computers in the 1970s used ticker tape read-outs.  This is an oddly archaic computer for such a futuristic spaceship to have, but it works to great comic effect, in keeping with the general suspicion and distrust of computers Adams expresses thoughout this series of books.