The advent of machines capable of recognizing human speech has been anxiously anticipated for many years. Prior to 1950, experiments were based upon the idea that language could be analyzed by syntax (the formal structure of a language) and semantics (the meanings of the individual words). Early speech recognition researchers were convinced that if all the proper word meanings and rules of grammar were stored inside a computer, the machine would be able to effectively translate languages. Unfortunately, more than $20 million dollars was spent by the military and various other government agencies on this type of research--all of which failed miserably. In the 1950s the Bell System began experimenting with a system that would allow telephone numbers to be spoken into receivers instead of being dialed, but that project also failed. Many of the problems encountered involved handling variances in accent, pronunciation, background noise or...