The U.S. military provides training and work for over 2.5 million people. The branches of the military are: Army, Navy, Air Force, and Marine Corps. The Coast Guard is now part of the U.S. Department of Homeland Security. Military training can prepare enlistees and officers for excellent careers in or out of the military.

Enlisted personnel (volunteers) make up about 85% of the Armed Forces. Officers make up the remaining 15%. Officers usually have a bachelor's or master's degree. Here we discuss the various roles, or careers, military personnel can have - keep in mind that enlisted personnel fill the rank-and-file jobs, and officers are usually in management or supervisory positions.

• Administrative personnel assist the military in keeping accurate information, including reports, operations, procedures, and more. Many specialize in areas such as accounting, finance, legal operations, or transportation. Most qualify for a variety of jobs in their specialization upon leaving active duty.
• Combat personnel are responsible for the planning and execution of combat missions. Most specialize in type of operation or weapon system. The field is good preparation for a career in the military, but can also be applied to police work, intelligence agencies, and more.
• Construction jobs include the building and repair of bridges, facilities, and much more. Electronic and electrical equipment repair personnel work on the electrical equipment that is so essential to military operations. These fields are good preparation for construction and repair work on the outside.
• Engineering, science, and technical jobs require specialized advanced training in areas such as emergency management, environmental health and safety (inspecting military facilities), and intelligence gathering.
• Healthcare encompasses medical professionals and their assistants. Most personnel specialize in a field, such as laboratory testing or ultrasound equipment operation. Once on the outside, personnel may need additional training and/or certification to practice medicine. em>Human resources specialists recruit and provide placement for personnel.
• Machine operation/production technicians operate the heavy equipment, tools, and machinery needed in military operations.
• Media/public affairs personnel handle public relations and also offer translation, interpretation, and cultural information services.
• Protective service personnel provide emergency response to disasters; enforce laws; and maintain food standards. The field is good preparation for fields such as police work, air traffic control, firefighting, and food service.
• Transportation/material handling specialists manage the transportation of people and goods. Possible later occupations include pilot, boat operator, or transportation specialist.
• Vehicle/machinery mechanics repair and maintain equipment, aircraft, ships, and engines. Most specialize in areas such as aircraft, automotive, marine, or HVAC. The field is good preparation for related work after active duty.

Work conditions vary considerably. Pay varies by qualifications, total years of service, and rank. Interested students may consult this Bureau of Labor Statistics.

Most personnel receive benefits such as health care, educational assistance, housing allowances, life insurance, and discounts on shopping. Those in military careers can usually retire after twenty years of service, and many retirees decide to start another career. Veterans are usually eligible for healthcare and other benefits.