Limited Duty Officer: due to the highly technical nature of some officer billets, the Marine Corps, Navy and Coast Guard employ a system of promoting proven senior enlisted members to the ranks of commissioned officers. They fill a need that is similar to, but distinct from that filled by warrant officers (to the point where their accession is through the same school). While warrant officers remain technical experts, LDOs take on the role of a generalist, like that of officers commissioned through more traditional sources. LDOs are limited, not by their authority, but by the types of billets they are allowed to fill. However, in recent times they have come to be used more and more like their more-traditional counterparts.
The rank of General of the Armies is considered senior to General of the Army, but was never held by active duty officers at the same time as persons who held the rank of General of the Army. It has been held by two people: John J. Pershing who received the rank in 1919 after World War I and George Washington who received it posthumously in 1976 as part of the American Bicentennial celebrations. Pershing, appointed to General of the Armies in active duty status for life, was still alive at the time of the first five-star appointments during World War II and was thereby acknowledged as superior in grade by seniority to any World War II–era Generals of the Army. George Washington's appointment by Public Law 94-479 to General of the Armies of the United States was established by law as having "rank and precedence over all other grades of the Army, past or present", making him not only superior to Pershing, but superior to any grade in the Army in perpetuity.
As of 2017, the U.S. spends about US$610 billion annually to fund its military forces and Overseas Contingency Operations. Put together, the U.S. constitutes roughly 40 percent of the world's military expenditures. The U.S. Armed Forces has significant capabilities in both defense and power projection due to its large budget, resulting in advanced and powerful technologies which enables a widespread deployment of the force around the world, including around 800 military bases outside the United States. The U.S. Air Force is the world's largest air force, the U.S. Navy is the world's largest navy by tonnage, and the U.S. Navy and the U.S. Marine Corps combined are the world's second largest air arm. In terms of size, the U.S. Coast Guard is the world's 12th largest naval force. 
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."
Jump up ^ Iversen, Amy C.; Fear, Nicola T.; Simonoff, Emily; Hull, Lisa; Horn, Oded; Greenberg, Neil; Hotopf, Matthew; Rona, Roberto; Wessely, Simon (2007-12-01). "Influence of childhood adversity on health among male UK military personnel". The British Journal of Psychiatry. 191 (6): 506–511. doi:10.1192/bjp.bp.107.039818. ISSN 0007-1250. PMID 18055954.
The Verbal Expression (VE) score is used to determine qualifications for many military jobs in all the branches, and it’s used to help determine your AFQT score. To compute your VE score, the military adds the number correct (1 point per correct answer) of the Paragraph Comprehension (PC) and the Word Knowledge (WK) subtests and then compares the results to the info in the following table.