In the middle of this chart are the "Integrated Resources", which define the core data structure definitions. These include:
On the left is "EXPRESS", the language in which the core data structure definitions are written.
On the top are the "Application Protocols", which are application specific views of the Integrated Resources in a clearly defined context. Examples shown in the chart are:
On the right is "Conformance Testing", use for translator and application certification. Elements shown for this are:
On the bottom are the "Implementation Specifications", used to transfer data. Elements shown for this are: