The Vision and Technical Foundations of Ubiquitous Computing Friedemann Mattern Continuing technical advances will soon lead to an abundance of very small and very cheap microprocessors, which are equipped with sensors and have wireless communication capabilities. Information processing will then become ubiquitous and will permeate almost every type of object. We illustrate the vision of Mark Weiser, the visionary behind ubiquitous computing, and describe its technical foundation and current trends. We also give a brief overview of its implications for privacy and outline possible applications. Keywords: ubiquitous computing, pervasive computing, sensors, embedded processors, networking, information appliances.