This is the CodeSystem that contains all the codes in ActivityDefinitionCategory (http://terminology.hl7.org/CodeSystem/activity-definition-category) and ActivityDefinitionCategory (http://terminology.hl7.org/CodeSystem/activity-definition-category). E.g. what you have to deal with if you get resources containing codes in either of them
Generated Narrative: CodeSystem 8f4cb24f-6ed6-40dc-8ea3-5def435c64b4-23
This code system http://hl7.org/fhir/comparison/CodeSystem/8f4cb24f-6ed6-40dc-8ea3-5def435c64b4-23 defines codes, but no codes are represented here