a simulation of a military operation intended to train military commanders or to demonstrate a situation or to test a proposed strategy

a game of skill and strategy, like Risk, Stratego or even Chess

a simulation, by whatever means, of a military operation involving two or more opposing forces, using rules, data, and procedures designed to depict an actual or assumed real life situation

an abstract simulation of a mass combat. The term "war game" may also be used to describe other highly abstract simulations, such as political or economic models, which affect and are affected by the actions of the game's characters. Usually such a model is operated by a GM specially delegated to that task.

the test of a nation's ability to fight an actual war. War games are practice for a real war and simulate them in a number of ways. Some war games are conducted entirely on computer.

War Game is a children's novel about World War I. Written by Michael Foreman in 1993, the story describes a group of four young men (Will, Freddie, Billy, and Lacey) who are eager to go for "the grand adventure". The story goes from training in England, to the arrival in France, to the famed Christmas Truce, to the Battle of the Somme.