There have been attempts to produce a military strength index: this is an example taken from a Credit Suisse report in September 2015.[32] The factors under consideration for that military strength indicator and their total weights were: number of active personnel in the army (5%), tanks (10%), attack helicopters (15%), aircraft (20%), aircraft carriers (25%), and submarines (25%). It was practically impossible to make an estimation of the actual training of the armed forces. [33] These were the results:
The military organization is characterized by a strict hierarchy divided by military rank, with ranks normally grouped (in descending order of authority) as officers (e.g. Colonel), non-commissioned officers (e.g. Sergeant), and personnel at the lowest rank (e.g. Private Soldier). While senior officers make strategic decisions, subordinated military personnel (soldiers, sailors, marines, or airmen) fulfil them. Although rank titles vary by military branch and country, the rank hierarchy is common to all state armed forces worldwide.

Personnel may be posted to bases in their home country or overseas, according to operational need, and may be deployed from those bases on exercises or operations anywhere in the world. During peacetime, when military personnel are generally stationed in garrisons or other permanent military facilities, they mostly conduct administrative tasks, training and education activities, technology maintenance, and recruitment.

The Armed Services Vocational Aptitude Battery (ASVAB) test is used by each branch of the military to determine a military recruit’s aptitude in ten different areas. The ASVAB test helps assign new recruits into career fields they may be well-suited for, but the ASVAB should not be considered an IQ test. It is a multiple-aptitude battery that measures developed abilities and helps predict future academic and occupational success in the military. The ASVAB test is also administered to millions of high school and post-secondary students making it one of the most widely used tests in the world.
There are 65 MEP joint services locations across all 52 states and in Puerto Rico. If you do not live close enough to a MEP, your recruiter will advise you to take the test at one of the MET sites which are located in many Federal government buildings, armories and Reserve stations. With multiple locations across the country to choose from, you won’t have to travel far to take this all-important first step toward a military career.
The CAT-ASVAB is a computer-based exam that is only provided at Military Entrance Processing Stations (MEPS) for enlistment purposes. The test is customized based on the taker’s answers, so if one question is answered correctly, the next one will be more difficult. This exam is timed, although users have the option of pacing themselves throughout the exam. However, it is not possible to go back through the test and check answers or change responses after they have been submitted. The CAT-ASVAB is broken down into 10 subparts, including basics such as arithmetic and verbal skills as well as auto information, electronics, shop, and mechanical knowledge.

There are many misconceptions about what it’s like to serve in the U.S. military. If you don’t know any soldiers personally, you might think of the military as a place for infantry, trudging though rough terrain and loading giant artillery. Although that may have been true in the past, today’s military offers many opportunities that aren’t readily apparent to the typical high school graduate. For example, there are jobs in aviation mechanics, medicine, and accounting. There are also peacekeeping and humanitarian efforts by the United States military that require skills in verbal and written communication. Taking the exam can help you determine if you would be well-suited to one of these occupations.

Each year, many high school and postsecondary students take the free Armed Services Vocational Aptitude battery (ASVAB).  The ASVAB is the most widely used multiple-aptitude test battery in the world.  It consists of eight tests that measure your skills and abilities in the following areas:  General Science; Arithmetic Reasoning; World Knowledge; Paragraph Comprehension; Mathematics Knowledge; Electronics Information; Auto and Shop Information; Mechanical Comprehension.
Additionally, all services except for the Air Force have an active warrant officer corps. Above the rank of warrant Officer One, these officers may also be commissioned, but usually serve in a more technical and specialized role within units. More recently, they can also serve in more traditional leadership roles associated with the more recognizable officer corps. With one notable exception (Army helicopter and fixed-wing pilots), these officers ordinarily have already been in the military often serving in senior NCO positions in the field in which they later serve as a warrant officer as a technical expert. Most Army pilots have served some enlisted time. It is also possible to enlist, complete basic training, go directly to the Warrant Officer Candidate School at Fort Rucker, Alabama and then on to flight school.
Test scores provide only one measure of your skills and abilities.  Test scores and grades, combined with information about your interests, values, skills, and achievements may help you select appropriate occupations for career exploration.  As you explore careers, you can compare your skills with the skill requirements of occupations in which you are interested.