In addition to the AFQT, the military also includes additional composite scores, often called 'line scores.' These scores are based on variations of the ASVAB's ten subtests and are required for certain military careers. For example, an Army Clerical (CL) score is determined by looking at an individual's Word Knowledge (WK), Paragraph Comprehension (PC), Arithmetic Reasoning (AR) and Mathematics Knowledge (MK) scores. Note that the subtests considered for different careers can vary depending on the military branch.
These scores include your Armed Forces Qualification Test (AFQT) score as well as your scores on each of the 9 individual subtests that make up the ASVAB.  When you get your report, the most important score you will want to look for first is your AFQT score.  This score determines your eligibility to serve in the military and to enlist in the U.S. Marines you need to have achieved a score of at least 32.
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.
The ASVAB is a series of timed aptitude tests that are used to classify selected candidates into appropriate job roles as well as ultimately decide the eligibility of candidates for US military service.  In other words, perform poorly on this test and you could severely limit your opportunities in the military or even prevent yourself from serving.
The Student ASVAB is the most flexible of the exams. It is typically provided to high school students to help them assess their skills, job prospects, potential military positions, or college majors. The ASVAB for students is essentially the same as the MET ASVAB exam, only students are not necessarily testing for positions within the military. The students’ school counselors examine their scores and help them decide on what to do after graduating from high school. This test is still an important component of a student’s education because it can help them identify their strengths and weaknesses and help set them on the right track for their future career goals.