Computer printers; computer programs; computers, electronic data processing machines, electrical and electronic apparatus and instruments, instructional and teaching apparatus, modems, accoustic couplers, disc drives, electric and electronic printing machines and plotting machines, visual display units, keyboards and keypads, computer memory devices; computer interface devices; parts and fittings included in class 9 for all the aforesaid goods; magnetic tapes, discs, cards and wires, data carriers bearing or incorporating machine readable data