ISO/IEC/IEEE 31320-1:2012 identifies the basic components of Integration Definition 0 (IDEF0) syntax (the drawn, visual elements of the language and how they may be used together) and IDEF0 semantics (what it means when the visual elements are used together in specific, allowable ways), specifies the rules that govern the use of these modelling components, and describes the types of diagrams used in an IDEF0 model. ISO/IEC/IEEE 31320-1:2012 identifies and discusses the model pages with which each diagram in an IDEF0 model is associated and discusses specific features found in an IDEF0 diagram. It describes IDEF0 reference expressions and IDEF0 diagram feature references. It also presents an abstract formalization of the IDEF0 language.