is a state of conflict
between relatively large groups of people (such as nations
, social groups
), which is characterized by the use of armed lethal violence
or upon civilians
. Other terms for war, which often serve as euphemisms
, include armed conflict, hostilities, and police action
A common perception of war is a series of military campaigns between at least two or more opposing sides involving a dispute over sovereignty, territory, resources, ideology or a host of other issues. A war to liberate an occupied country is sometimes characterised as a "war of liberation", while a war between internal elements of the same state may constitute a civil war.
Aside from humans and their primate brethren, ants are the only other species known to exhibit such behavior on a large scale.
A battle is a single engagement fought between two or more parties, wherein each party or aligned group will seek to defeat their opponent. Battles are most often fought during military campaigns and can usually be well defined in time, space and action. Wars are generally the continuum of a related series of battles and are guided by strategy, whereas individual battles are the stage on which tactics are employed.
Military history is the recording and analysis of those events in the history of humanity that fall within the category of organised armed conflict, and that relate to the institutions and organizations that prosecute such conflict.
Blitzkrieg was an operational-level military doctrine which employed mobile forces attacking with speed and surprise to prevent an enemy from organising a coherent defence. Conceived in the years after World War I, it grew out of the earlier doctrine of "Fire and Infiltration". It was used by the German Wehrmacht in World War II. Operations early in the war—the invasions of Poland, France, and the Soviet Union—were highly effective, owing to surprise, enemy unpreparedness and superior German military doctrines. Methods of blitzkrieg operations centered on using manoeuvre rather than attrition to defeat an opponent. The blitzkrieg thus first and foremost required a concentration of armoured assets at a focal point, closely supported by mobile infantry, artillery and close air support assets. These tactics required the development of specialised support vehicles, new methods of communication, new tactics, and the presence of a decentralised command structure. Broadly speaking, blitzkrieg operations required the development of mechanised infantry, self-propelled artillery and engineering assets that could maintain the rate of advance of the tanks. In combat, blitzkrieg forced slower defending forces into defensive pockets that were encircled and then destroyed by following German infantry.