From HomoExcelsior

Also known as "embodied virtuality". Computers that are an integral, invisible part of people's lives. In some ways the opposite of virtual reality, in which the user is absorbed into the computational world. With ubiquitous computing, computers take into account the human world rather than requiring humans to enter into the computer's methods of working. See Mark Weiser, "The Computer for the 21st Century" Scientific American Sept. 1991, Jim Morrison and Ubiquitous Computing at Xerox Parc.