What's the difference between services and arms?

According to the main combat space, tasks and weapons and equipment of the army, the service is the basic category of the army.

As far as its composition is concerned, the service is a basic service category divided according to the main weapons and equipment, combat tasks and technical and tactical characteristics.

Second, the scope is different:

A service includes one or more branches, or one or more branches constitute a service. Different services can include the same branch. For example, aviation is the main body of the air force, and the navy can also have aviation units shared by other services, such as signal soldiers, radar soldiers, meteorological soldiers and health soldiers.

Arms, the army mainly includes infantry, armored force (tank force), artillery, army air defense force, army aviation force, electronic countermeasure force, engineering force, signal force, chemical defense force, etc. The navy mainly includes submarine force, surface warship force, naval aviation force, naval coastal defense force and marine corps. The air force mainly includes aviation, antiaircraft artillery, ground-to-air missile troops and radar.

There are differences in service division standards.

Judging from the current military practice of countries around the world, although the definition of "cross-service" is adopted in joint operations, due to the differences in their respective development histories and military doctrines, the standards for the division of services in various countries are not consistent.

For example, the Marine Corps belongs to the naval sequence in our army and is independent of the three major services in the US military; Airborne troops belong to the air force sequence in our army, but the US military is incorporated into the army sequence. Another example is that some national armies have air defense units, but our army does not have this service. Therefore, if "cross-clothing" is used as the dividing standard, it must be that the same action here and now belongs to "common", but it was not "common" there at that time.

Baidu Encyclopedia-Military Service