This document specifies requirements and provides recommendations for the selection, usage and dependencies of visual user-interface elements and their application. This document is concerned with visual software components of interactive systems to make human-system interaction usable. This document is applicable regardless of a fixed, portable or mobile interactive system, or cross-device use. It does not provide detailed coverage of the methods and techniques required for design of visual user-interface elements. This document does not address implementation (e.g. graphical design of elements) and interaction details for specific input methods or technologies. It does not cover decorative user-interface elements that are intended to address solely aesthetic (hedonic) qualities in the user interface e.g. background images.