A. Wearable computing facilitates a new form of human--computer interaction based on a small body--worn computer system that is always on and always ready and accessible. In this regard, the new computational framework differs from that of hand held devices, laptop computers and personal digital assistants (PDAs). The "always ready" capability leads to a new form of synergy between human and computer, characterized by long-term adaptation through constancy of user--interface. The formal definition, given by Webster encyclopedia, may be found at /fundamentals/