Redundant Encoding

A design principle that communicates information through multiple visual channels simultaneously — such as colour plus shape, pattern, text label, or position — so that no single channel is required for comprehension. Redundant encoding is a foundational recommendation for CVD accessibility, ensuring that colour-coded information remains accessible when colour distinctions are not perceived. Effective redundant encoding uses meaningful secondary cues appropriate to the context, rather than simply adding symbols that re-encode the colour itself.