Such a disappearance is a fundamental consequence not of technology, but of human psychology. Whenever people learn something sufficiently well, they cease to be aware of it. When you look at a street sign, for example, you absorb its information without consciously performing the act of reading..

Computer scientist,economist, and Nobelist Herb Simon calls this phenomenon "compiling"; philosopher Michael Polanyi calls itthe "tacit dimension"; psychologist TK Gibson calls it "visual invariants"; philosophers Georg Gadamer and Martin Heidegger call it "the horizon" and the "ready-to-hand", John Seely Brown at PARC calls it the"periphery".

All say, in essence, that only when things disappear in this way are we freed to use them withoutthinking and so to focus beyond them on new goals. The idea of integrating computers seamlessly into the world at large runs counter to a number of present-day trends. "Ubiquitous computing" in this context does not just mean computers that can be carried to the beach,jungle or airport. Even the most powerful notebook computer, with access to a worldwide information network,still focuses attention on a single box. By analogy to writing, carrying a super-laptop is like owning just one very important book. Customizing this book, even writing millions of other books, does not begin to capture the real power of literacy. Furthermore, although ubiquitous computers may employ sound and video in addition to text and graphics, that does not make them "multimedia computers." Today's multimedia machine makes the computer screen into a demanding focus of attention rather than allowing it to fade into the background.

Mark Weiser, Scientific American 1991, coining the term "ubiquitous computing"