War

War is a state of armed conflict between states, governments, societies and informal paramilitary groups, such as mercenaries, insurgents and militias.

A mercenary, sometimes known as a soldier of fortune, is an individual who takes part in military conflict for personal profit, is otherwise an outsider to the conflict, and is not a member of any other official military.

It is generally characterized by extreme violence, aggression, destruction, and mortality, using regular or irregular military forces.

Of the deaths in 2013, roughly 842,000 were attributed to self-harm (suicide), 405,000 to interpersonal violence, and 31,000 to collective violence (war) and legal intervention.

It is generally characterized by extreme violence, aggression, destruction, and mortality, using regular or irregular military forces.

A military is a heavily-armed, highly organised force primarily intended for warfare, also known collectively as armed forces.

Total war is warfare that is not restricted to purely legitimate military targets, and can result in massive civilian or other non-combatant suffering and casualties.

Total war is warfare that includes any and all civilian-associated resources and infrastructure as legitimate military targets, mobilizes all of the resources of society to fight the war, and gives priority to warfare over non-combatant needs.

The scholarly study of war is sometimes called polemology, from the Greek polemos, meaning "war", and -logy, meaning "the study of".

War studies, sometimes called polemology, is the multi-disciplinary study of war.

Asymmetric warfare (or asymmetric engagement) is war between belligerents whose relative military power differs significantly, or whose strategy or tactics differ significantly.

A cold war is a state of conflict between nations that does not involve direct military action but is pursued primarily through economic and political actions, propaganda, acts of espionage or proxy wars waged by surrogates.

Total war is warfare that is not restricted to purely legitimate military targets, and can result in massive civilian or other non-combatant suffering and casualties.

Under the law of war, it is referred to civilians who perished or suffered wounds as a result of wartime acts.

Conventional warfare is a form of warfare conducted by using conventional weapons and battlefield tactics between two or more states in open confrontation.

Nuclear warfare breaking out in August 1988, when nuclear arsenals were at peak level, and the aftermath thereof, could have reduced human population from 5,150,000,000 by 1,850,000,000 to 3,300,000,000 within a period of about one year, according to a projection that did not consider "the most severe predictions concerning nuclear winter".

Nuclear warfare (sometimes atomic warfare or thermonuclear warfare) is a military conflict or political strategy in which nuclear weaponry is used to inflict damage on the enemy.

In times of war, belligerent countries can be contrasted with neutral countries, and non-belligerents.

In military operations, economic warfare may reflect economic policy followed as a part of open or covert operations, cyber operations, information operations during or preceding wartime.

Weapons are used to increase the efficacy and efficiency of activities such as hunting, crime, law enforcement, self-defense, and warfare.

The earliest evidence for prehistoric warfare belongs to the Mesolithic cemetery Site 117, which has been determined to be approximately 14,000 years old.

Prehistoric warfare refers to war that occurred between societies without recorded history.

Total war is warfare that is not restricted to purely legitimate military targets, and can result in massive civilian or other non-combatant suffering and casualties.

They are persons, such as combat medics and military chaplains, who are members of the belligerent armed forces but are protected because of their specific duties (as currently described in Protocol I of the Geneva Conventions, adopted in June 1977); combatants who are placed hors de combat; and neutral persons not involved in fighting for one of the belligerents involved in a war.

For instance, the Thirty Years' War (1618-1648) had about the same number of casualties per capita as World War I, although it was higher during World War II (WWII).

The Thirty Years' War was a war fought primarily in Central Europe between 1618 and 1648.

War usually results in significant deterioration of infrastructure and the ecosystem, a decrease in social spending, famine, large-scale emigration from the war zone, and often the mistreatment of prisoners of war or civilians.

A prisoner of war (POW) is a person, whether a combatant or a non-combatant, who is held captive by a belligerent power during or immediately after an armed conflict.

The Human Security Report 2005 documented a significant decline in the number and severity of armed conflicts since the end of the Cold War in the early 1990s.

The study reported major worldwide declines in the number of armed conflicts, genocides, military coups, and international crises, as well as in the number of battle-related deaths per armed conflict.

In War Before Civilization, Lawrence H. Keeley, a professor at the University of Illinois, says approximately 90–95% of known societies throughout history engaged in at least occasional warfare, and many fought constantly.

The attrition rate of numerous close-quarter clashes, which characterize warfare in tribal warrior society, produces casualty rates of up to 60%, compared to 1% of the combatants as is typical in modern warfare.

Military personnel subject to combat in war often suffer mental and physical injuries, including depression, posttraumatic stress disorder, disease, injury, and death.

Posttraumatic stress disorder (PTSD) is a mental disorder that can develop after a person is exposed to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, or other threats on a person's life.

It is generally characterized by extreme violence, aggression, destruction, and mortality, using regular or irregular military forces.

The ǃKung people were described as 'The Harmless People' in a popular work by Elizabeth Marshall Thomas in 1958, while Lawrence Keeley's 1996 War Before Civilization suggested that regular warfare without modern technology was conducted by most groups throughout human history, including most Native American tribes.

In the 21st century, worldwide anti-war movements occurred in response to the United States invasion of Afghanistan and Iraq.

The Iraq War was a protracted armed conflict that began in 2003 with the invasion of Iraq by a United States-led coalition that overthrew the government of Saddam Hussein.

Most wars have resulted in significant loss of life, along with destruction of infrastructure and resources (which may lead to famine, disease, and death in the civilian population).

The definition distinguishes from persons whose duties involves risking their lives to protect the public at large from hazardous situations such as terrorism, riots, conflagrations, or wars.

War leads to forced migration causing potentially large displacements of population.

As concerns a belligerent's losses in proportion to its prewar population, the most destructive war in modern history may have been the Paraguayan War (see Paraguayan War casualties).