The United States Army, US Marine Corps, US Navy, US Air Force, US Coast Guard, US Public Health Service Commissioned Corps, and National Oceanic and Atmospheric Administration Commissioned Corps are the top Uniformed services with specific and sometimes similar tasks to perform on daily basis.
The United States Army
The United States Army is the oldest branch of the top 7 uniformed services. It is also the most senior in rank among the military service departments. It was formed in the year 1775 to fight the American Revolutionary War that lasted until 1783. It is one of the three military departments of the Armed Forces. As at the year 2017, there were about 475,000 soldiers enlisted in the US Army. You can get more details about the United States Army on this site.
The US Marine Corps
This is the branch of US Armed forces that conduct expeditionary and amphibious operations. This military branch works with the Army, Air Force, and the Navy to protect the sea from territorial invasion. The Marine Corp started operations in 1834 and works closely with the US Navy. The Marine Corps is responsible for the deployment of marine warships all around the world. As at the year 2017, roughly 186,000 active personnel have been employed into the US Marine Corps.
The United States Navy
The US Navy is involved in Naval Warfare and it remains the largest Navy and most capable naval organization in the world today. They also deploy some of the largest aircraft carrier fleets, in and outside of the country. Presently there are about 330,000 Naval officers on active duty with more than 100,000 personnel on reserve. The US Navy works closely with the Air force and the Marines for all kinds of combats, especially on the air and sea.
The United States Air Force
The Air Force is an entity of the Armed forces that is involved in all aerial and space battles for the United States of America. It was initially formed as part of the US army in 1907 but became a separate branch of the Armed Forces in 1947. Though it remains the youngest part of the armed forces it is fourth in rank in the precedence order. The United State Air Force is the largest air force in the world and remains the most technologically advanced.
The United States Coast Guard
The United State Coastal Guard {USCG} is one of the arms of the US Armed Forces that enforces laws related to the coastal seas. It is multi-mission in nature, and quite unique from all other uniformed arms. It works on both domestic and international waters, and also operates under the Department of Homeland Security.
The United States Coastal Guard is one of the oldest organizations in the armed forces. It was established in the year 1790 and one other major duties it performs is to conduct search and rescue for humans, air crafts and other significant things declared missing in the territorial waters. Currently, the USCG has more than 41,000 employed uniformed men and women. In addition to these, there are over 31,000 Auxiliaries. The USCG currently has about 250 coastal and ocean-moving ships alongside icebreakers, tenders, and tugs.
The United States Public Health Service Commissioned Corps
It was founded in 1889 and its role is to complement laws enacted in the healthcare and Medical services. It is one of the 7 uniformed service providers in the Armed Forces and it comprises of commissioned officers with no warrant officers enlisted. For this reason, the officers of the United States Health Service Commissioned Corps are non-combatant uniformed men. The commissioned Corps members do wear the same Uniforms with the Navy. The Corps is also under the direct supervision and management of the Public Health Services. This commissioned Corp has more than 1.3 million active personnel and about 820,000 Reserves, making it the largest armed forces component.
There are over 6,700 uniformed members of the Corp, minus the members and the commission is currently headed by a Surgeon General who reports directly to the Ministry of Health. The main duties of the Public Health Service Commissioned Corps are to protect the safety and health of military and civilians working in the armed forces. Sometimes, they are deployed into war grounds to provide treatment for wounded military men and women.
The National Oceanic and Atmospheric Administration Commissioned Officer Corps
This is the youngest arm of the Armed Forces. It was established in the year 1970, and currently has 379 officers, with 16 ships and 10 aircraft. This arm of the armed forces currently operates under the National Oceanic and Atmospheric Administration (NOAA), which is currently being overseen by the Ministry of Commerce. It is considered as one of the two public health commissioned Corps, with no combatant officers enrolled. Though the predecessor organization- NOAA, was established in 1917, the Commissioned Officer Corps was not established until 1970.
The main duties of the Commissioned Corps are to provide assistance in services such as engineering, sciences, fisheries, Meteorology, and Oceanography. The commissioned corps members are also involved in diving operations and the management of research projects conducted in the sea and other aquatic bodies. The Corps activities are funded by the government directly and the Corp reports directly to the ministry of health.
In conclusion, there are several other uniformed military services in the country that are worth mentioning, they tend to be less significant and their staff strengths seem to be smaller than the largest 7 described above. The top 5 largest uniformed groups are known to bear ammunitions while the last two are not authorized for the same. Aside from the Army, Navy, Air Force, Marine Corps, and the Coastal Guards, the personnel of other uniformed service providers are not normally trained for combat situations, except for few emergency training they may receive if they have to be deployed outside of the country and to places where their lives might be subjected to heavy artilleries.