What is AAC?

Augmentative: communication supports that increase the effectiveness of natural speech and speech approximations.  

Alternative: communication supports in the absence of functional speech. It is a replacement to their vocal abilities.

Common forms:   Messages may be represented as picture symbols, icons, photos, and words.  These messages may be displayed on communication cards, in communication books, single message buttons, fixed boards with voice recordings (called simple digitized systems), computer-type systems with computerized speech (speech generating devices).  People may use a combination of paper based and electronic based systems depending on their needs.  Gestures, manual signs and video clips may also be a part of a persons system.