The fog of war (Nebel des Krieges) is the uncertainty in situational awareness experienced by participants in military operations. The term seeks to capture the uncertainty regarding one's own capability, adversary capability, and adversary intent during an engagement, operation, or campaign. Military forces try to reduce the fog of war through military intelligence and friendly force tracking systems. The term has become commonly used to define uncertainty mechanics in wargames. The word "fog" (Nebel), but not the exact phrase, in reference to 'uncertainty in war' was introduced by the Prussian military analyst Carl von Clausewitz in his posthumously published book, Vom Kriege (1832), the English translation of which was published as On War (1873): War is the realm of uncertainty; three quarters of the factors on which action in war is based are wrapped in a fog of greater or lesser uncertainty. A sensitive and discriminating judgment is called for; a skilled intelligence to scent out the truth. It has been pointed out that von Clausewitz does not use the exact phrase "fog of war", and also uses multiple similar metaphors, such as "twilight" and "moonlight", to describe a 'lack of clarity'. The first known use of the exact phrase in text dates to 1896 in a book titled The Fog of War by Sir Lonsdale Augustus Hale, where it is described as "the state of ignorance in which commanders frequently find themselves as regards the real strength and position, not only of their foes, but also of their friends." The fog of war is a reality in all military conflict. Precision and certainty are unattainable goals, but modern military doctrine suggests a trade-off of precision and certainty for speed and agility. Militaries employ command and control (C2) systems and doctrine to partially alleviate the fog of war. The term also applies to the experience of individual soldiers in battle: often cited is the pure confusion of direction, location, and perspective on a battlefield.