Cap Badges and Insignia in US and UK and Commonwealth countries.

In the United States, Cap Badges denote the Service, being, Army, Navy and USMC. There was no Air Force as a separate entity until 1947. During World War Two the Air Force was part of the Army and was called the US Army Air Force or USAAF. Some countries such as Canada and Israel have integrated Armed Forces with no separate divisions for the Army, Navy, Marines and Air Force. In the United Kingdom and Commonwealth countries, the tradition is to have the Branch of Service Insignia on the cap, for example, Engineers, Tank regiment etc. The Royal Army medical Corps is not an independent regiment, and its personnel are assigned to their respective branch of service. They generally do not carry firearms, and they are not engaged in active military roles. Both in the US and the UK, Officers and often Warrant Officers have different Insignia and caps. In the US, Branch of service insignia such as cavalry and infantry, are worn on the lower lapel on both sides. US side-caps have the rank rather than Service.