Thus, in the vision of ubiquitous computing, computer-based systems anticipate and respond to the needs of their users to control everyday environments such as homes, workplaces, and automobiles. For example, in a home environment, a pervasive computing system could be used to support a variety of tasks, including turning lights on and off as people move from one room to another, automatically generating shopping lists as items are

removed from the refrigerator, and learning a person’s favorite television programs and recording them automatically. Within the area of healthcare, pervasive computing techniques could lead to systems in which devices like thermometers and sphygnometers immediately transmit information to a patient’s electronic medical records. They could provide a physician in the hospital with instant access on a secure PDA to the up-to-date records of a current patient. Pervasive computing could make it possible for a cognitively impaired person to have his activities monitored and to receive a reminder if he forgot to take his medicine or needed directions to get back home should he get lost walking around his neighborhood. Pervasive computing techniques could also make it possible for a physically disabled person to readily control her environment, with doors opening automatically as her wheelchair approached and the oven responding to commands spoken into a small, wearable microphone.