Combat Arms are troops who participate in direct combat, including infantry, armor, artillery, and other specialized units involved in ground operations to confront and defeat enemy forces.
Combat Support units provide operational assistance to combat units, enhancing their effectiveness through various functions such as logistics, reconnaissance, fire support, and medical services.
Sustainment, or combat service support, encompasses entities that deliver both direct and indirect support services necessary for the ongoing operational effectiveness of combat units.
Disbanded units are all inactive military formations that have been officially dissolved and no longer participate in operational activities.