Screen readers

A screen reader is a software application which, rather than presenting web content visually, converts text into 'synthesised speech' allowing user to alternatively listen to content. In more accurate terms – content displayed in screen is sent to standard output, whether a video monitor is present or not. Interpretations are then synthesised to the user with text-to-speech, sound icons, or a Braille output device. Screen readers are a form of assistive technology (AT) which are essential to people who are blind, as well as useful to people who are visually impaired,illiterate, or have a learning disability.

Microsoft Windows operating systems have included the Microsoft Narrator light-duty screen reader since Windows 2000. Apple Inc. Mac OS X, iOS, and tvOS include VoiceOver, a feature-rich screen reader, while Google's Android includes Google Text-to-Speech, also on Android, Samsung devices have Samsung Text-to-Speech. The console-based Oralux Linux distribution ships with three console screen-reading environments: Emacspeak, Yasr, and Speakup. BlackBerry 10 devices such as the BlackBerry Z30 include a built-in screen reader. There is also a free screen reader application for older less powerful BlackBerry (BBOS7 and earlier) devices.

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Wikipedia