All of the branches work together during operations and joint missions in Unified Combatant Commands, under the authority of the Secretary of Defense with the typical exception of the Coast Guard. Each of the Unified Combatant Commands is headed by a Combatant Commander, a senior commissioned officer who exercises supreme command authority per 10 U.S.C. § 164 over all of the forces, regardless of branch, within his geographical or functional command. By statute, the chain of command flows from the President to the Secretary of Defense to each of the Combatant Commanders.[22] In practice, the Chairman of the Joint Chiefs of Staff often acts as an intermediary between the Secretary of Defense and the Combatant Commanders.
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]
Armed Forces & Society (AFS) a quarterly publication with international scope publishes articles on civil-military relations, veterans, force effectiveness and diversity, military culture, officer education and training, military institutions, ethics, unit cohesion, military families, peacemaking, privatization, public opinion and conflict management. The editors and contributors include political scientist, sociologist, psychologists, legal scholars, historians and economists as well as specialists in military organization and strategy, and peacekeeping.
By military department, $146.9 billion was allocated for the Department of the Army, $168.8 billion for the Department of the Navy, $161.8 billion for the Department of the Air Force and $102.8 billion for DoD-wide spending.[6] By function, $138.6 billion was requested for personnel, $244.4 billion for operations and maintenance, $118.9 billion for procurement, $69.0 billion for research and development, $1.3 billion for revolving and management funds, $6.9 billion for military construction and $1.3 billion for family housing.[6]
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).
Military law introduces offences not recognised by civilian courts, such as absence without leave (AWOL), desertion, political acts, malingering, behaving disrespectfully, and disobedience (see, for example, Offences against military law in the United Kingdom).[23] Penalties range from a summary reprimand to imprisonment for several years following a court martial.[23] Certain fundamental rights are also restricted or suspended, including the freedom of association (e.g. union organizing) and freedom of speech (speaking to the media).[23] Military personnel in some countries have a right of conscientious objection if they believe an order is immoral or unlawful, or cannot in good conscience carry it out.
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. 
×