naturally with the way we interact with the physical world, especially when they take advantage of our well-learned repertoire of physical actions (e.g. grasping, pushing, and lifting) [Rogers et al, 2002].
The Fourth Machine Age
Kaj Grønback and Peter Krogh  from the Centre of Pervasive Computing (CfPC) in Denmark are trying to identify the elements of the new state; they refer to the article “The End of the Mechanical Age” by Ezio Manzini. Manzini argues that the premise of mechanization has come to an end, and that is because it is no longer adequate to simplify and clarify complex phenomena, especially if in such systems the observer is always regarded as external to the system observed. The article concludes with the idea that we are no longer confronted with a given taxonomy of materials and techniques, but with a continuum of possibilities. Grønback and Krogh focus on this continuum that has triggered a significant increase of the integration of physical artefacts with computation. And even though “Mixed Reality” is usually used to describe such cases they prefer notions like “pervasive” and “ubiquitous”[Weiser,1993], because such notions are better for describing what is actually happening. “The notion of MR is an abstract idea of what information technologies enhancement of physical objects does to our perception of reality”.
Following their argument they relate Ezio Manzini’s article to Reyner Banham’s  “Theory and Design in the first Machine Age”. They assume that we are on the border of the fourth machine age. The first machine age was characterized by large and heroic machines like cars, airplanes and heavy industry. The second utilized the mechanics of the first to invent small and pervasive mechanics like the refrigerator, the vacuum cleaner and other household machines. The third machine age is characterized by the emergence of the computer originally designed for specialized use in work settings. Today the
Using Everyday Objects as Communication tools