This document discusses principles of universal design and multi-sensory systems. It covers using multiple senses like sight, sound, touch, and potentially taste and smell with technology. Specific technologies are explored like speech recognition and synthesis, non-speech sounds like earcons and auditory icons, handwriting recognition, and gestures. Applications for users with disabilities are also covered like using different modalities for visual impairments, hearing impairments, physical impairments, and more. Finally, it notes the importance of considering different age groups and cultural factors in design.