Fog of war varies according to the level at which participants are engaged:
Grand strategic : Ambiguity is related to the political intent, capabilities and logistical strengths of an adversary. Sources of information include diplomatic intelligence, secret (or special) intelligence, strategic modeling and data derived from open source intelligence. Affected participants seek to understand intent of and political motivations. Outcomes at this level may encompass military action but are more concerned with socio-political and economic outcomes from which it might cascade if left unattended.
Military strategic : Militarily, the ambiguity experienced at this level relates to the structure, strength, capability, and disposition of own and adversary offensive and defensive assets. Own-force ambiguity can be caused by failure to report material deficiencies or an unwillingness to escalate concerns, leading to an optimistic view of own capabilities. Adversary ambiguity may be a result of inaccurate intelligence, sources being subverted or deceived, or adversary intelligence presenting a superior picture allowing one's decision cycle to be compromised. In addition, if unanticipated situations occur they can hamper the execution of long term planning.
Operational : Within the operational theatre the commander undertakes tasks as directed by the Military Strategic level, ambiguity continues to relate to adversary capability and intent but is coupled with own directive ambiguity, the commander not having the full sight of the strategic imperative. As operational tempo increases at this level the ambiguity experienced by the commander is susceptible to delays in communication of the tactical situation and the ebb and flow of own force, and adversary force interaction. The commander seeks to penetrate the fog of war through significant use of reconnaissance assets and a comprehensive Joint Operational Picture.
Tactical : Ambiguity stems from several factors at the tactical level, both by deliberate means by the enemy (including active deception and/or electronic attack on communications and sensors) as well as factors inherent to battle resulting in lack of comprehension by commanders as to the tactical environment, the logistic status of their own units, how they are interacting with each other, or their intentions. This lack of comprehension can stem from many factors, individually or in combination, such as poor reconnaissance; inaccurate intelligence; or faulty communication. The tempo of decision making at the tactical level is much greater than at other levels, increasing the risk of escalating ambiguity as assumptions build and resources are allocated based on those assumptions.
Experience :The practical experience of the fog of war is most easily demonstrated in the tactical battlespace. It may include military commanders' incomplete or inaccurate intelligence about the enemy's numbers, disposition, capabilities, and intent, regarding features of the battlefield, and incomplete knowledge of the state of their own forces. Fog of war is caused by the limits of reconnaissance, by the enemy's feints and disinformation, by delays in receiving intelligence and difficulties passing orders, and by the difficult task of forming a cogent picture from a very large (or very small) amount of diverse data.
When a force engages in battle and the urgency for good intelligence increases, so does the fog of war and chaos of the battlefield, while military units become preoccupied with fighting or are lost (either destroyed by enemy fire or literally lose their way), reconnaissance and liaison elements become unavailable, and sometimes real fog and smoke obscure vision. Much of the modern military's technological efforts, under the rubric of command and control seek to reduce the fog of war. Although even the most advanced technology cannot eliminate it, military theorists continue to develop ways to reduce it.
The term "fog of war" has become jargon in military games, in the more limited sense of enemy units or characters being hidden from the player. By extension, "Fog of War" is also used to describe the limited view distance of many first person shooters, where unlimited view is considered either bad for gameplay or, more often, because of technical limitations, in that a Fog of War allows for the rendering of a smaller part of the game area. This, however, is often referred to as one's "line of sight". In the Commands & Colors series of boardgames, designed by Richard Borg, the fog of war is simulated by a deck of cards from which the players can pick their actions. Different sides of the battle usually have a different number of cards (each one describing a possible action) and players have to choose which card to use. It often happens that the best action imaginable in that moment is impossible to do because the player does not have a useful card for it. This is to simulate the difficulty of in-battle communication in the heat of the moment.
