War films are a film genre concerned with warfare, usually about naval, air or land battles, sometimes focusing instead on prisoners of war, covert operations, military training or other related subjects. At times war films focus on daily military or civilian life in wartime without depicting battles. Their stories may be fiction, based on history, docudrama, biographical, or even alternate history fiction.

The term anti-war film is sometimes used to describe films which bring to the viewer the pain and horror of war, often from a political or ideological perspective.

John Belton identified four narrative elements of the war film within the context of Hollywood production: a) the suspension of civilian morality during times of war, b) primacy of collective goals over individual motivations, c) rivalry between men in predominantly male groups as well as marginalization and objectification of women, and d) depiction of the reintegration of veterans. Film scholar Kathryn Kane has pointed out similarities between the war film genre and the Western. Both genres use opposing concepts like war and peace, civilization and savagery. War films usually frame World War II as a conflict between good and evil as represented by the Allied forces and Nazi Germany whereas the Western portrays the conflict between "civilized" settlers and the "savage" indigenous peoples. Film historian Jeanine Basinger argues that a sub-genre, the World War II combat film, emerged in 1943. This sub-genre depicts military action whereas the war film genre need not portray armed combat.

War is an organized, armed, and often a prolonged conflict that is carried on between states, nations, or other parties typified by extreme aggression, social disruption, and usually high mortality. War should be understood as an actual, intentional and widespread armed conflict between political communities, and therefore is defined as a form of political violence. The set of techniques used by a group to carry out war is known as warfare. An absence of war (and other violence) is usually called peace.

In 2003, Nobel Laureate Richard E. Smalley identified war as the sixth (of ten) biggest problems facing the society of mankind for the next fifty years. In the 1832 treatise On War, Prussian military general and theoretician Carl von Clausewitz defined war as follows: "War is thus an act of force to compel our enemy to do our will."

While some scholars see warfare as an inescapable and integral aspect of human culture, others argue that it is only inevitable under certain socio-cultural or ecological circumstances. Some scholars argue that the practice of war is not linked to any single type of political organization or society. Rather, as discussed by John Keegan in his History of Warfare, war is a universal phenomenon whose form and scope is defined by the society that wages it. Another argument suggests that since there are human societies in which warfare does not exist, humans may not be naturally disposed for warfare, which emerges under particular circumstances. The ever changing technologies and potentials of war extend along a historical continuum. At the one end lies the endemic warfare of the Paleolithic^{[citation needed]} with its stones and clubs, and the naturally limited loss of life associated with the use of such weapons. Found at the other end of this continuum is nuclear warfare, along with the recently developed possible outcome of its use, namely the potential risk of the complete extinction of the human species.

A film, also called a movie or motion picture, is a series of still or moving images. It is produced by recording photographic images with cameras, or by creating images using animation techniques or visual effects. The process of filmmaking has developed into an art form and industry.

Films are cultural artifacts created by specific cultures, which reflect those cultures, and, in turn, affect them. Film is considered to be an important art form, a source of popular entertainment and a powerful method for educating – or indoctrinating – citizens. The visual elements of cinema give motion pictures a universal power of communication. Some films have become popular worldwide attractions by using dubbing or subtitles that translate the dialogue into the language of the viewer.

Films are made up of a series of individual images called frames. When these images are shown rapidly in succession, a viewer has the illusion that motion is occurring. The viewer cannot see the flickering between frames due to an effect known as persistence of vision, whereby the eye retains a visual image for a fraction of a second after the source has been removed. Viewers perceive motion due to a psychological effect called beta movement.