ABSTRACT
Many research areas are attempting to address this input deciency, but they can mainly be seen in terms of two basic approaches:
Improving the language that humans can use to interact with • computers
Increasing the amount of situational information, or context, that is • made available to computers
e rst approach tries to improve interaction by allowing the human user to communicate in a much more natural manner. is type of communication is still very explicit, in that the computer only knows what the user tells it. With natural input techniques such as speech and gestures, no other information besides the explicit input is available to the computer. As we know from human-human interactions, situational information
such as facial expressions, emotions, past and future events, the existence of other people in the room, and relationships to these other people are crucial to understanding what is occurring. e process of building this shared understanding between two people is called grounding (Clark and Brennan, 1991). Since both human participants in such an interaction share this situational information, there is no need to make it explicit. is helps to explain why a driver nds it easier to talk to a passenger than to someone on a cell phone-with the passenger, there is grounding without explicit communication. However, this need for explicitness does exist in human-computer interactions, because the computer does not share this implicit situational information or context. e goal of context-aware computing is to use context as an implicit cue to enrich the impoverished interaction from humans to computers, making it easier to interact with computers.
