The President of the United States is the Commander in Chief, who is responsible for all final decisions. The Secretary of the Department of Defense (DoD) has control over the military and each branch - except the Coast Guard, which is under the Dept. of Homeland Security. With over 2 million civilian and military employees, the DoD is the world's largest "company."
You often hear people say something like, "I got a 70 on the ASVAB." What they are talking about is the ASVAB AFQT score or Armed Forces Qualification Test Score. Many people think the AFQT score is the overall ASVAB score, but that's not correct. In fact, the AFQT score is derived from only four of the nine ASVAB subtests: Paragraph Comprehension (PC), Word Knowledge (WK), Mathematics Knowlege (MK), and Arithmetic Reasoning (AR).
First, the ASVAB measures your accumulated knowledge in different areas. So if you are currently in school, stay focused and study hard. Your overall knowledge gained in school will most likely be reflected in your ASVAB score. Second, though accumulated knowledge is important, you may be able to raise your score by preparing specifically for the ASVAB, especially in areas where you are weak. Various study guides are available for this purpose (listed left).

AFQT scores are grouped into five main categories based on the percentile score ranges. Categories III and IV are divided into subgroups because the services sometimes use this chart for internal tracking purposes, enlistment limits, and enlistment incentives. Based on your scores, the military decides how trainable you may be to perform jobs in the service.
In addition to the ASVAB's AFQT, each branch has military occupational specialty, or MOS, scores. Combinations of scores from the nine tests are used to determine qualification for a MOS. These combinations are called "aptitude area scores", "composite scores", or "line scores". Each of the five armed services has its own aptitude area scores and sets its own minimum composite scores for each MOS.
Just as the President, the Secretary of Defense, and the Secretary of Homeland Security, are in charge of the entire military establishment, maintaining civilian control of the military, so too are each of the Defense Department's constitutive military departments headed by civilians. The four DoD branches are organized into three departments, each with civilian heads. The Department of the Army is headed by the Secretary of the Army, the Department of the Navy is headed by the Secretary of the Navy and the Department of the Air Force is headed by the Secretary of the Air Force. The Marine Corps is organized under the Department of the Navy, however it is still considered a separate and equal service. The Coast Guard is under the Department of Homeland Security and receives its operational orders from the Secretary of Homeland Security. However, the Coast Guard may be transferred to the Department of the Navy by the President or Congress during a time of war, thereby placing it within the DoD.[19]

The Arithmetic Reasoning section of the test measures your ability to solve arithmetic word problems. You may be asked questions such as “If the tire of a car rotates at a constant speed of 552 times in 1 minute, how many times will the tire rotate in half an hour?” Therefore, reviewing common math key words associated with each operation is recommended. For example, if you see the key words “in all,” the problem deals with addition. If the problem asks you to “find the difference,” you are being asked to subtract. If a question asks “how many times” per day or week, you know you are dealing with multiplication. If it asks “how many in each,” you should be thinking about division. The CAT-ASVAB has 16 questions in 39 minutes; the paper-and-pencil version has 30 questions in 36 minutes.
The AFQT is often mistakenly called the “overall ASVAB score.” You commonly hear someone say, “I got a 67 on the ASVAB,” or “My ASVAB score was 92.” That’s not correct; it implies that the AFQT is derived from all nine subtests of the ASVAB, and it’s not. The AFQT score is computed from just four of the ASVAB subtests that measure your math and communicative ability.
Arguably, the greatest invention that affected not just the military, but all society, after adoption of fire, was the wheel, and its use in the construction of the chariot. There were no advances in military technology, until, from the mechanical arm action of a slinger, the Greeks, Egyptians, Romans, Persians, Chinese, etc., development the siege engines. The bow was manufactured in increasingly larger and more powerful versions, to increase both the weapon range, and armour penetration performance. These developed into the powerful composite and recurve bows, and crossbows of Ancient China. These proved particularly useful during the rise of cavalry, as horsemen encased in ever-more sophisticated armour came to dominate the battlefield.
These relationships are seen from the perspective of political-military relations, the military-industrial complex mentioned above, and the socio-military relationship. The last can be divided between those segments of society that offer support for the military, those who voice opposition to the military, the voluntary and involuntary civilians in the military forces, the populations of civilians in a combat zone, and of course the military's self-perception.
Less hot under the collar than This Year's Model, Armed Forces was partly inspired by Elvis Costello and the Attractions' 1978 American tour. The songs are set to deceptively poppy arrangements that use plinky Abba keyboards ("Oliver's Army," a hit single about mercenaries), Beatles-ish devices (the fade on "Party Girl"), and whimsical waltz-time signatures ("Sunday's Best") to mask their core cynicism. "Goon Squad," "Busy Bodies," and "Accidents Will Happen" are among Costello's most melodically powerful songs to this point, leading the way to the masterful Get Happy!!. --Barney Hoskyns

The Armed Forces Qualification Test (AFQT) is used by all of the Services to determine if an applicant is eligible for the military. Four of the ASVAB subtests are combined to form the AFQT. It measures general cognitive ability and is composed of verbal and mathematics subtests. AFQT scores are grouped into categories for reporting purposes. The table below shows the AFQT categories and the percentile score ranges corresponding to the categories. Applicants that score in AFQT category IIIA or higher may qualify for enlistment incentives.