This part of the 62541 series specifies the standard representation of Programs as part of the OPC Unified Architecture and its defined information model. This includes the description of the NodeClasses, standard Properties, Methods and Events and associated behaviour and information for Programs. The complete address space model including all NodeClasses and Attributes is specified in IEC 62541-3. The services such as those used to invoke the Methods used to manage Programs are specified in IEC 62541-4.