Natural language commands can provide improvements in efficiency but are increasingly being used in desktop environments to enhance usability. For many users it's easier and more natural to produce spoken commands than to remember the location of functions in menus and dialog boxes. Speech technology is unlikely to make existing user interfaces redundant any time soon, but spoken commands provide an elegant complement to existing interfaces. Speech dictation systems are now affordable and widely available. These rates substantially exceed the typing ability of most people.
Speech synthesis can enhance applications in many ways.
Speech synthesis of text in a word processor is a reliable aid to proof-reading, as many users find it easier to detect grammatical and stylistic problems when listening rather than reading. Speech synthesis can provide background notification of events and status changes, such as printer activity, without requiring a user to lose current context. Applications which currently include speech output using pre-recorded messages can be enhanced by using speech synthesis to reduce the storage space by a factor of up to 1000, and by removing the restriction that the output sentences be defined in advance. In many situations where keyboard input is impractical and visual displays are restricted, speech may provide the only way to interact with a computer. For example, surgeons and other medical staff can use speech dictation to enter reports when their hands are busy and when touching a keyboard represents a hygiene risk.