Jan Fischer, American Soldier In His Military Life

Military tactics concerns itself with the methods for engaging and defeating an enemy in direct combat. Military tactics are usually used by units over hours or days, and are focused on the specific, close proximity tasks and objectives of squads, companies, battalions, regiments, brigades and divisions and their naval and air equivalents.
One of the oldest military publications is The Art of War by the Chinese philosopher Sun Tzu. Written in the 6th century BCE, the 13-chapter book is intended as military instruction and not as military theory, but has had a huge influence on Asian military doctrine, and from the late 19th century, on European and United States military planning. It has even been used to formulate business tactics, and can even be applied in social and political areas.
The Classical Greeks and the Romans wrote prolifically on military campaigning. Among the best-known Roman works are Julius Caesar's commentaries on the Gallic Wars and the Roman Civil war - written about 50 BC.
Two major works on tactics come from the late Roman period: Taktike Theoria by Aelianus Tacticus and De Re Militari ("On military matters") by Vegetius. Taktike Theoria examined Greek military tactics, and was most influential in the Byzantine world and during the Golden Age of Islam.