Temporal encoding

The representation of information through change over time within a spatial substrate. In the visual design space, temporal encoding corresponds to animation — a point or shape moving, appearing, or changing on screen. In the sonic design space, temporal encoding is the primary means of conveying information, as all sound unfolds over time. Temporal encoding has significant accessibility implications: animation can be a barrier for users with vestibular disorders or cognitive disabilities (addressed by the WCAG pause, stop, hide criterion), while time-based sonic content may be too fast for some users to process. Captions and audio descriptions are themselves temporal encodings that must be synchronised with the primary media. The concept helps formalise why time-based content presents unique accessibility challenges compared to static content.