The Technology Related Assistance to Individuals with Disabilities Act of 1988 described an assistive technology device as "any item, piece of equipment, or product system, whether acquired commercially off the shelf, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities."
Assistive technologies can be "high tech" and "low tech:" from canes and lever doorknobs to voice recognition software and augmentative communication devices (speech generating devices).
Electronic Fluency Devices are devices intended to help improve the fluency of people with stutters. They do this by playing the sound of the user's own voice back into their ear, slightly altered.
There are two main types of Electronic Fluency Devices :
Delayed Auditory Feedback (DAF)- Delayed Auditory Feedback devices play the user's voice back delayed by a fraction of a second. DAF devices may resemble hearing aids or headphones with a microphone. There are also apps that can use DAF on phone calls.
Frequency Altered Feedback (FAF)- Frequency Altered Feedback devices are similar to DAF but rather than delaying the user hearing their own voice, they change the pitch at which the user hears their own voice.