The first home computers which were developed in the 1980s stored data on magnetic tape. Following this, some manufacturers used cartridges rather than disks, and these are still used in many games machines (eg the Sega Megadrive). One reason for this is that cartridges can be encrypted to protect software from illegal copying, but they are more expensive to produce than floppy disks or CD Roms to produce. (Cotton, Bob, and Oliver, Richard, The Cyberspace Lexicon, Phaidon Press, London, 1994, p34)