in contrast, includes acts such as self-mutilation. Collective Unlike the other two broad categories, the subcategories of collective violence suggest possible motives for violence committed by larger groups of individuals or by states. Collective violence that is committed to advance a particular social agenda includes, for example, crimes of hate committed by organized groups, terrorist acts and mob violence. Political violence includes war and related violent conflicts, state violence and similar acts carried out by armed groups. There may be multiple determinants of violence against civilians in such situations. Economic violence includes attacks motivated by economic gain—such as attacks carried out with the purpose of disrupting economic activity, denying access to essential services, or creating economic division and fragmentation. Clearly, acts committed by domestic and subnational groups can have multiple motives. Slow violence is a long-duration form of violence which is often invisible (at least to those not impacted by it), such as environmental degradation, pollution and climate change. Warfare War is a state of prolonged violent large-scale conflict involving two or more groups of people, usually under the auspices of government. It is the most extreme form of collective violence. War is fought as a means of resolving territorial and other conflicts, as war of aggression to conquer territory or loot resources, in national self-defence or liberation, or to suppress attempts of part of the nation to secede from it. There are also ideological, religious and revolutionary wars. Since the Industrial Revolution the lethality of modern warfare has grown. World War I casualties were over 40 million and World War II casualties were over 70 million. Interpersonal Interpersonal violence is divided into two subcategories: Family and intimate partner violence—that is, violence largely between family members and intimate partners, usually, though not exclusively, taking place in the home. Community violence—violence between individuals who are unrelated, and who may or may not know each other, generally taking place outside the home. The former group includes forms of violence such as child abuse and child corporal punishment, intimate partner violence and abuse of the elderly. The latter includes youth violence, random acts of violence, rape or sexual assault by strangers, and violence in institutional settings such as schools, workplaces, prisons and nursing homes. When interpersonal violence occurs in families, its psychological consequences can affect parents, children, and their relationship in the short- and long-terms. Child maltreatment Child maltreatment is the abuse and