Means of warfare refers to the weapons and weapon systems by means of which violence is exercised against the enemy.
Any item of equipment supplied by States or armed groups to their armed forces or members so that in an armed conflict they can take violent action against the enemy, and whose use, within the limits justified by military necessity and the rules of international humanitarian law, is legitimate in time of war.
Weapons may be classified according to their nature and effects.
International humanitarian law
- states that the right of the parties to the conflict to choose methods or means of warfare is not unlimited and that in the study, development, acquisition or adoption of a new weapons a party is under an obligation to determine whether its employment would, in some or all circumstances, be prohibited;
- prohibits weapons of a nature to cause superfluous injury or unnecessary suffering or having excessively injurious or indiscriminate effects.
The use of certain weapons is prohibited or restricted. It is, however, impossible to dissociate the lawfulness or unlawfulness of weapons from the lawfulness or unlawfulness of the way they are used. This applies particularly to land, sea, and above all air bombardment. Weapons may be divided into handheld weapons for cutting, thrusting and striking, firearms and weapons of mass destruction.
See also Conventional Weapons; Incendiary weapons; Laser weapons; Remnants of war; Chemincal Weapons; Biological weapons; Chemical weapons; Nuclear weapons;
Chapter 9, III. Means and methods of warfare
Chapter 9, III. 2. Prohibited or restricted use of weapons
Iran/Iraq, UN Security Council Assessing Violations of International Humanitarian Law
Case Study, Armed Conflicts in the former Yugoslavia 
UN, Statement of a Special Rapporteur on Drone Attacks
General Assembly, The use of drones in counter-terrorism operations
ICRC, International Humanitarian Law and the challenges of contemporary armed conflicts in 2015 [paras 224-226, 273-274, 280, 291, 292]
Israel/Palestine, Operation Protective Edge (Gaza, 13 June - 26 August 2014)
ICRC, Statement - War in Cities ; What is at Stake?
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