International humanitarian law (IHL), also referred to as the laws of armed conflict, is the law that regulates the conduct of war. It is a branch of international law that seeks to limit the effects of armed conflict by protecting persons who are not participating in hostilities and by restricting and regulating the means and methods of warfare available to combatants.
The First Geneva Convention of 1864.
Combatant is the legal status of a person entitled to directly participate in hostilities during an armed conflict, and may be intentionally targeted by an adverse party for their participation in the armed conflict. Combatants are not afforded immunity from being directly targeted in situations of armed conflict and can be attacked regardless of the specific circumstances simply due to their status, so as to deprive their side of their support.
Afghan National Army soldiers conducting a patrol in 2011, during the War in Afghanistan. They would be considered combatants in the war.