Some of the special technologies can make the web accessible come in the form of free downloadable plug-ins, software that has to be purchased and even hardware that is added on to your computer. Each type of special technology brings its own set of issues related to web page design. A screen reader is a software program that allows a blind person to listen to text on the screen and identify some graphics like buttons on a toolbar or icons on the Desktop. A person hears the information from a speech synthesizer or the computer's sound card. Also, for those of you who are physically in Tucson, you can see screen readers and braille devices and other adaptive devices at the University of Arizona Disability Resource Center, on Second Street.
Some people use a refreshable Braille display rather than listening to the information.
A Braille display is not like a computer screen. Usually, it is placed near or under the keyboard. The screen reader sends the information on the screen to the Braille display. A Braille display is helpful to persons who are deaf and blind or to those who work at jobs that require them to talk on the phone to customers. Source Iowa Department for the Blind.