International humanitarian law (IHL) is a set of rules which seeks to limit the effects of armed conflict. It restricts the means and methods of warfare permitted to combatants and protects those who are not, or are no longer, actively taking part in fighting. In particular, the right of the parties to an armed conflict to choose means and methods of warfare is limited by basic rules of IHL relating to the conduct of hostilities, many of which are found in Protocol I additional to the 1949 Geneva Conventions on the protection of victims of international armed conflicts (Additional Protocol I). Treaty and customary IHL also set prohibitions or limitations on the employment of certain weapons, means and methods of warfare. States are required to review the legality of new weapons, means and methods of warfare before deploying them to the armed forces. This obligation is found in Article 36 of Additional Protocol I, to which the vast majority of States are party.