Conversing with computers - naturally

For the past 20 years or so, a great deal of research has been aimed at enabling users of computers to communicate with their machines by voice only, instead of by keyboards and visual display units. What at first appeared to be relatively easy, getting a computer to talk with a human-like voice and making it able to respond appropriately when spoken to, has turned out to be extremely difficult. It is so difficult that we can now confidently predict that it will be several decades before fully natural, freeflowing conversation can take place between people and machines. Only now are we beginning to develop systems that perform the task in an acceptable way, though in certain restricted areas conversation with computers is already with us.