Digital audio technology allows you to control a computer simply by giving spoken commands, rather than using a mouse or a keyboard. You can also input text to the computer by reading it aloud. This can be much quicker than typing it in, especially if you are not a skilled typist, and it can also be of assistance to physically impaired users. The technology behind this is often referred to as Speech Recognition. To use speech recognition you need an audio input device, such as a microphone (often built into a headset), a sound card, and speech recognition software, such as Dragon Naturally Speaking, that converts speech into text or commands. Speech recognition technology can be used to interact with various programs including word processors or Internet browsers. Some operating systems, such as Windows 7, offer direct support fro speech recognition. Recent Apple iPhones can be controlled using an advanced speech recognition interface known as Siri.
Computers can also output data as speech rather than text. This is known as Speech Synthesis and is of obvious benefit to visually-impaired users or those who suffer from reading difficulties, such as dyslexia. Some operating systems, including Windows 7, incorporate speech synthesis facilities, as do programs like Adobe Reader.
A screen reader is a program that can read anything displayed on the screen and convert it directly to sound. Your computer must be equipped with a sound card and speakers or headphones to support speech synthesis. Many modern motherboards incorporate a sound card, so there is no need to add one as a separate device.
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