Physical computing is all around us--from interactive displays at museums to "puff sensors" that aid the physically challenged. With a multiple book buying audience, this book doesn't require a specific background or technical experience. It is designed to help make a more interesting connection between the physical world and the computer world. The audience size is comparable to that of the Robot builder market. In addition to this audience, physical computing is also taught at several universities across the US. This book is a great source of information and knowledge for anyone interested in bridging the gap between the physical and the virtual. The people at Apple Computer saw it first when they started marketing "computers for the rest of us." They discovered that computers were useful beyond business and engineering applications. They found that graphic artists, musicians, and even children also wanted to use computers but they needed a different interface. The resulting Graphical User Interface reached many more different types of people but it stopped when it reached the fingertips resting on their keyboard and mouse. The computer revolution continued in the 1990's with the advent of the Web increasing the bandwidth between computers but the bandwidth between the person and the computer was still constrained by the old physical interface. The slogan for Physical Computing to continue the computer revolution would be "computers for the rest of me." An example of Physical Computing would be this project. A medical assistant was continually frustrated by the number of quadriplegic patients he saw who had to use expensive, difficult-to-learn tools for operation of computers,household devices, and other everyday tools. He had seen "puff sensors," in which the patient blew into a tube in particular patterns to type, but knew they could be improved. For his final project in physical computing, he demonstrated a working puff-sensor interface for typing that he built with off-the-shelf parts, much cheaper than the commercial models, and with a more flexible interface.

The computer revolution has made it easy for people with little to no technical training to use a computer for such everyday tasks as typing a letter, saving files, or recording data. But what about more imaginative purposes such as starting your car, opening a door, or tracking the contents of your refrigerator? "Physical Computing" will not only change the way you use your computer, it will change the way you think about your computer-how you view its capabilities, how you interact with it, and how you put it to work for you. It's time to bridge the gap between the physical and the virtual-time to use more than just your fingers to interact with your computer. Step outside of the confines of the basic computer and into the broader world of computing.

Tom Igoe is a professor at New York Universitys Interactive Telecommunications program within the Tisch School of the Arts. He has vastly expanded Physical Computing into the areas of performance, embedded applications and sculpture. Tom has personally

Introduction 1. Shopping 2. Circuits 3. Microcontroller 4. Programming 5. The Big 4 Schematics, Programs and Transducers 6. Communicating Between Computers Appendices: A: Features to Consider for Your Microcontroller B: Handy Reference Card C: CD-ROM