Somewhat earlier, in medieval China, gunpowder had been invented, and was increasingly used by the military in combat. The use of gunpowder in the early vase-like mortars in Europe, and advanced versions of the long bow and cross bow, which all had armour-piercing arrowheads, that put an end to the dominance of the armoured knight. After the long bow, which required great skill and strength to use, the next most significant technological advance was the musket, which could be used effectively, with little training. In time, the successors to muskets and cannon, in the form of rifles and artillery, would become core battlefield technology.
The profession of soldiering as part of a military is older than recorded history itself. Some of the most enduring images of the classical antiquity portray the power and feats of its military leaders. The Battle of Kadesh in 1274 BC was one of the defining points of Pharaoh Ramses II's reign, and is celebrated in bas-relief on his monuments. A thousand years later, the first emperor of unified China, Qin Shi Huang, was so determined to impress the gods with his military might, he was buried with an army of terracotta soldiers.[1] The Romans were dedicated to military matters, leaving to posterity many treatises and writings, as well as a large number of lavishly carved triumphal arches and victory columns.

The obligations of military employment are many. Full-time military employment normally requires a minimum period of service of several years; between two and six years is typical of armed forces in Australia, the UK and the US, for example, depending on role, branch, and rank.[19][20][21] Some armed forces allow a short discharge window, normally during training, when recruits may leave the armed force as of right.[22] Alternatively, part-time military employment, known as reserve service, allows a recruit to maintain a civilian job while training under military discipline at weekends; he or she may be called out to deploy on operations to supplement the full-time personnel complement. After leaving the armed forces, recruits may remain liable for compulsory return to full-time military employment in order to train or deploy on operations.[22][21]
After enlistment, new recruits undergo basic training (also known as "boot camp" in the Marine Corps, Navy and Coast Guard), followed by schooling in their primary Military Occupational Specialty (MOS), rating and Air Force Specialty Code (AFSC) at any of the numerous training facilities around the United States. Each branch conducts basic training differently. The Marine Corps send all non-infantry MOS's to an infantry skills course known as Marine Combat Training prior to their technical schools. Air Force Basic Military Training graduates attend Technical Training and are awarded their Air Force Specialty Code (AFSC) at the apprentice (3) skill level. All Army recruits undergo Basic Combat Training (BCT), followed by Advanced Individual Training (AIT), with the exceptions of cavalry scouts, infantry, armor, combat engineers and military police recruits who go to One Station Unit Training (OSUT), which combines BCT and AIT. The Navy sends its recruits to Recruit Training and then to "A" schools to earn a rating. The Coast Guard's recruits attend basic training and follow with an "A" school to earn a rating.

There are several different authorized pay grade advancement requirements in each junior-enlisted rank category (E-1 to E-3), which differ by service. Enlistees in the Army can attain the initial pay grade of E-4 (specialist) with a four-year degree, but the highest initial pay grade is usually E-3 (members of the Army Band program can expect to enter service at the grade of E-4). Promotion through the junior enlisted ranks occurs after serving for a specified number of years (which can be waived by the soldier's chain of command), a specified level of technical proficiency or maintenance of good conduct. Promotion can be denied with reason.
Sergeant Leigh Ann Hester became the first woman to receive the Silver Star, the third-highest U.S. decoration for valor, for direct participation in combat. In Afghanistan, Monica Lin Brown was presented the Silver Star for shielding wounded soldiers with her body.[43] In March 2012, the U.S. military had two women, Ann E. Dunwoody and Janet C. Wolfenbarger, with the rank of four-star general.[44][45] In 2016, Air Force General Lori Robinson became the first female officer to command a major Unified Combatant Command (USNORTHCOM) in the history of the United States Armed Forces.[46]
Standard Scores are scores that have a fixed mean and standard deviation in the population of examinees. A Standard Score indicates how many units of the standard deviation a particular score is above or below the mean. In the case of the ASVAB subtests, the mean is set to 50 and the standard deviation is set to 10. Thus, a Standard Score of 40 indicates that the examinee scored 1 standard deviation below the mean. A Standard Score of 70 indicates that the examinee scored 2 standard deviations above the mean. To learn more about how standard scores are derived and used, click here.
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