Voice recognition or speech recognition is the capability of a computer to recognize spoken words. Speaking can be used in lieu of typing or mouse clicking to input information to the computer. There are two major types of speech recognition programs: speech-to-text and command-and-control. Speech-to-text systems transfer spoken words into written words for use in applications such as word processing programs. Command-and-control systems interpret spoken words as commands, for example, to open a new program or save a file.

Speech recognition research began in the 1950s. IBM demonstrated its first voice recognition device at the 1962 World's Fair in Seattle. Shoebox was a bulky arithmetic calculator that could recognize numerical digits spoken into a microphone. Computers that could converse with humans were popularized by science fiction during the 1960s, appearing in the movie 2001: A Space Odyssey and the Star Trek television series. The actual computer technologies of...