Military science
History: Even until the Second World War, military science was written in English starting with capital letters, and was thought of as an academic discipline alongside physics, philosophy and the medical sciences. In part this was due to the general mystique that accompanied education in a world where, as late as the 1880s, 75% of the European population was illiterate. The ability by the officers to make complex calculations required for the equally complex "evolutions" of the troop movements in linear warfare that increasingly dominated the Renaissance and later history, and the introduction of the gunpowder weapons into the equation of warfare only added to the veritable arcana of building fortifications as it seemed to the average individual.
Until the early 19th century, one observer, a British veteran of the Napoleonic Wars, Major John Mitchell, thought that it seemed nothing much had changed from the application of force on a battlefield since the days of the Greeks. He suggested that this was primarily so because as Clausewitz suggested, "unlike in any other science or art, in war the object reacts".
Until this time, and even after the Franco-Prussian War, military science continued to be divided between the formal thinking of officers brought up in the "shadow" of the Napoleonic Wars and younger officers like Ardant du Picq who tended to view fighting performance as rooted in the individual's and group psychology and suggested detailed analysis of this. This set in motion the eventual fascination of the military organisations with application of quantitative and qualitative research to their theories of combat; the attempt to translate military thinking as philosophic concepts into concrete methods of combat.
Military implements, the supply of an army, its organization, tactics, and discipline, have constituted the elements of military science in all ages; but improvement in weapons and accoutrements appears to lead and control all the rest.
The breakthrough of sorts made by Clausewitz in suggesting eight principles on which such methods can be based, in Europe, for the first time presented an opportunity to largely remove the element of chance and error from command decision making process. At this time emphasis was made on the topography (including trigonometry), military art (military science), military history, organisation of the army in the field, artillery and the science of projectiles, field fortifications and permanent fortifications, military legislation, military administration and manoeuvres.
The military science on which the model of German combat operations was built for the First World War remained largely unaltered from the Napoleonic model, but took into the consideration the vast improvements in the firepower and the ability to conduct "great battles of annihilation" through rapid concentration of force, strategic mobility, and the maintenance of the strategic offensive better known as the Cult of the offensive. The key to this, and other modes of thinking about war, remained analysis of military history and attempts to derive tangible lessons that could be replicated again with equal success on another battlefield as a sort of bloody laboratory of military science. Few were bloodier than the fields of the Western Front between 1914 and 1918. The person who probably understood Clausewitz better than most, Marshal Foch, initially participated in events that nearly destroyed the French Army.
It is not, however, true to say that military theorists and commanders were suffering from some collective case of stupidity. Their analysis of military history convinced them that decisive and aggressive strategic offensive was the only doctrine of victory, and feared that overemphasis of firepower, and the resultant dependence on entrenchment would make this all but impossible, and leading to the battlefield stagnant in advantages of the defensive position, destroying troop morale and willingness to fight. Because only the offensive could bring victory, lack of it, and not the firepower, was blamed for the defeat of the Imperial Russian Army in the Russo-Japanese War. Foch thought that "In strategy as well as in tactics one attacks".
In many ways military science was born as a result of the experiences of the Great War. "Military implements" had changed armies beyond recognition with cavalry to virtually disappear in the next 20 years. The "supply of an army" would become a science of logistics in the wake of massive armies, operations and troops that could fire ammunition faster than it could be produced, for the first time using vehicles that used the combustion engine, a watershed of change. Military "organisation" would no longer be that of the linear warfare, but assault teams, and battalions that were becoming multi-skilled with the introduction of machine guns and mortars and, for the first time, forcing military commanders to think not only in terms of rank and file, but force structure.
Tactics changed, too, with infantry for the first time segregated from the horse-mounted troops, and required to cooperate with tanks, aircraft and new artillery tactics. Perception of military discipline, too, had changed. Morale, despite strict disciplinarian attitudes, had cracked in all armies during the war, but the best-performing troops were found to be those where emphasis on discipline had been replaced with display of personal initiative and group cohesiveness such as that found in the Australian Corps during the Hundred Days Offensive. The military sciences' analysis of military history that had failed European commanders was about to give way to a new military science, less conspicuous in appearance, but more aligned to the processes of science of testing and experimentation, the scientific method, and forever "wed" to the idea of the superiority of technology on the battlefield.
Currently military science still means many things to different organisations. In the United Kingdom and much of the European Union the approach is to relate it closely to the civilian application and understanding. For example, in Belgium's Royal Military Academy, military science remains an academic discipline, and is studied alongside social sciences, including such subjects as humanitarian law. The United States Department of Defense defines military science in terms of specific systems and operational requirements, and include among other areas civil defense and force structure.

Employment of military skills: In the first instance military science is concerned with who will participate in military operations, and what sets of skills and knowledge they will require to do so effectively and somewhat ingeniously.

Military organization: Develops optimal methods for the administration and organization of military units, as well as the military as a whole. In addition, this area studies other associated aspects as mobilization/demobilization, and military government for areas recently conquered (or liberated) from enemy control.

Force structuring: Force structuring is the method by which personnel and the weapons and equipment they use are organized and trained for military operations, including combat. Development of force structure in any country is based on strategic, operational, and tactical needs of the national defense policy, the identified threats to the country, and the technological capabilities of the threats and the armed forces.
Force structure development is guided by doctrinal considerations of strategic, operational and tactical deployment and employment of formations and units to territories, areas and zones where they are expected to perform their missions and tasks. Force structuring applies to all armed services, but not to their supporting organisations such as those used for defense science research activities.
In the United States force structure is guided by the table of organization and equipment (TOE or TO&E). The TOE is a document published by the U.S. Department of Defense which prescribes the organization, manning, and equipage of units from divisional size and down, but also including the headquarters of corps and armies.
Force structuring also provides information on the mission and capabilities of specific units, as well as the unit's current status in terms of posture and readiness. A general TOE is applicable to a type of unit (for instance, infantry) rather than a specific unit (the 3rd Infantry Division). In this way, all units of the same branch (such as infantry) follow the same structural guidelines which allows for more efficient financing, training, and employment of like units operationally.

Military education and training: Studies the methodology and practices involved in training soldiers, NCOs (non-commissioned officers, i.e. sergeants and corporals), and officers. It also extends this to training small and large units, both individually and in concert with one another for both the regular and reserve organizations. Military training, especially for officers, also concerns itself with general education and political indoctrination of the armed forces.

Military concepts and methods: Much of capability development depends on the concepts which guide use of the armed forces and their weapons and equipment, and the methods employed in any given theatre of war or combat environment.

Military history: Military activity has been a constant process over thousands of years, and the essential tactics, strategy, and goals of military operations have been unchanging throughout history. As an example, one notable maneuver is the double envelopment, considered to be the consummate military maneuver, notably  executed by Hannibal at the Battle of Cannae in 216 BCE, and later by Khalid ibn al-Walid at the Battle of Walaja in 633 CE.
Via the study of history, the military seeks to avoid past mistakes, and improve upon its current performance by instilling an ability in commanders to perceive historical parallels during battle, so as to capitalize on the lessons learned. The main areas military history includes are the history of wars, battles, and combats, history of the military art, and history of each specific military service.

Military strategy and doctrines: Military strategy is in many ways the centerpiece of military science. It studies the specifics of planning for, and engaging in combat, and attempts to reduce the many factors to a set of principles that govern all interactions of the field of battle. In Europe these principles were first defined by Clausewitz in his Principles of War. As such, it directs the planning and execution of battles, operations, and wars as a whole.