The Common domain of the Defense OSDK contains interfaces that serve as cross-cutting primitives shared across multiple domains. Rather than belonging to a single warfighting function, these interfaces represent foundational concepts — such as standard military symbology, reporting structures, and geographic locations — that are broadly applicable throughout the ontology.
Because common interfaces are domain-agnostic, object types from any domain can implement them. For example, the Named Location interface can be implemented by an area of operations in Mission Planning or a facility in Order of Battle, enabling workflows that operate on any named geographic location regardless of its domain of origin.