International humanitarian law (IHL) is also known as the law of armed conflict (LOAC) or the laws of war. IHL applies only in times of armed conflict, placing legal obligations on all warring parties. IHL norms are designed to put limits on the way belligerents conduct warfare. The main sources of IHL are the four Geneva Conventions and their additional protocols as well as customary law. The ICRC holds a specific mandate to promote the development of IHL. IHL contains limitations and prohibitions based on the fundamental norm of distinction between combatants and civilians, where only the former can be lawfully targeted. This core distinction yields key additional IHL rules, such as the prohibition of indiscriminate attacks and the prohibition of disproportionate attacks. IHL also aims at protecting certain categories of persons who do not, or no longer, take part in hostilities such as prisoners of war and civilians, and provide for the special protections of certain persons and objects, such as medical personnel, hospitals, cultural objects (e.g., mosques, churches) and objects essential to the survival of the civilian population (e.g., crops, water sources).