Introduction to Assistive Technologies

Assistive technology, also called accessibility aids, are tools added to computers to enhance accessibility. Common aids include:

• Screen Magnifiers: Enlarge areas of the screen for people with low vision.
• Screen Readers: Convert on-screen text to speech or Braille for the blind.
• On-screen Keyboards: Allow input via pointing methods for those unable to use standard keyboards.
• Keyboard Enhancements: Simplify key sequences and mouse control.
• Speech Recognition Programs: Enable voice control of computers.
• Alternative Input Devices: Provide non-standard ways to interact with computers, like eye-gaze or sip-and-puff systems.

Assistive Technologies for Physical Disabilities and RSI

Assistive Technology	Function Provided
Alternate Pointing Device	Enables mouse control for users with limited motor control, e.g., foot-operated mice, head-mounted devices, and eye-tracking systems.
Screen Keyboard	An on-screen keyboard used with alternate pointing devices.
Predictive Dictionary	Speeds up typing by predicting words and offering them in a list.
Speech Recognition	Allows users to control the interface or input text via speech.

Keyboard Enhancements

Feature	Function Provided
StickyKeys	Locks modifier keys, enabling single-finger operation of key combinations.
MouseKeys	Offers keyboard control of cursor movement and mouse functions.
RepeatKeys	Delays key repeat onset, aiding users with coordination challenges.
SlowKeys	Requires keys to be held down before acceptance, preventing accidental presses.
BounceKeys	Adds a delay between keystrokes to prevent system from accepting inadvertent presses.
ToggleKeys	Provides auditory feedback for locking key states, like Caps Lock.

Assistive Technologies for Low Vision and Blind Users

Assistive Technology	Function Provided
Screen Reader	Provides speech output or Braille display of text and limited graphics.
Braille Display	Displays on-screen text in Braille using a series of pins.
Text to Speech (TTS)	Converts electronic text into synthesized speech.
Magnification	Magnifies screen content, tracking input focus.

Assistive Technologies for Hearing Disabilities

Assistive Technology	Function Provided
Telecommunications Device for the Deaf (TDD)	Allows communication over phone lines using text terminals.
Closed Captioning	Provides text translation of spoken content in videos.
ShowSounds	Proposes visual translation of sound information, such as system beeps through screen flashes.