[C]opyright owners have most often been concerned to litigate against infringements when they perceive some intrusion on their commercial market. Thus an informal public/private distinction has developed which has assisted in determining what is likely to be a permissible act with a work. However digitisation of works, and more particularly the inclusion of works on a digital network, may render this distinction obsolete. Personal use may interfere with the copyright owner´s "public" market over which the owner seeks control. The same equipment that allows a work to be accessed also permits its dissemination.