Mobile communications havepermeated the globe in both business and social cultures. In only af ew short years, Japan aloneh ash ad more than ten million subscribers enter the mobilem arket. Such explosive popularity is an indication ofa strong commercial demand for communications in both the tethered and tetherless environments. Accompanying the vibrant growth in mobile communications is the growth in multimedia communications, includingthe Internet. Mobile and multime dia communications technologies are merging, making mobile computing ak ey phrasei n the coming advanced information communication era. Thegrowth i n these dynamic industries shows that achange in our chosen method of commu nications is already well advanced. Reading e mail and connecting to various information feeds have already become a part ofdaily business activities. We are trying to grasp theo verall picture of mobile computing. Its shape and form are just starting to appear as personal digital assistants (PDA), handheld personal computers (HPC), wireless data communication services, and com mercial software designed for mobile environments. We are at the cusp of vast popularization of "computers on the go." "Any time Anywhere Computing" provides the reader with an understand able explanationo ft he current developments and commercialization of mobile computing. Thec oret ec hnologies and applications needed to un derstand the industry are comprehensively addressed. Thebook emphasizes three infrastruc tures: (1) wireless communication network infrastructure, (2) terminal devices (or "computers on the go"), and (3) software middleware and architectures that support wireless and mobile computing.