A specification of the conventions for a particular representation element. Representation elements are instances of representation element kinds. For example, a cylinder is a representation kind for storage/database components, the Data Sources and Store on the RAG component diagram are representation elements of the “Storage/Database” kind. Different colors of “Data Sources” representation may highlight heterogeneity of the data sources - plain text, PDF, HTML. And monochromaticity of the “Store” representation element indicates homogeneity of the “Store” semantic element.