ABSTRACT
Ubiquitous computing, or ubicomp, is the term given to the third era of modern computing. e rst era was dened by the mainframe computer, a single large time-shared computer owned by an organization and used by many people at the same time. Second, came the era of the PC, a personal computer primarily owned and used by one person, and dedicated to them. e third era, ubiquitous computing, representative of the present time, is characterized by the explosion of small networked portable computer products in the form of smart phones, personal digital assistants (PDAs), and embedded computers built into many of the devices we own-resulting in a world in which each person owns and uses many computers. Each era has resulted in progressively larger numbers of computers becoming integrated into everyday life (Figure 1.1).
