UNSC Army

The UNSC Army  is a branch of the UNSC Defense Forces primarily responsible for land-based military operations.

Background
Little is known about the UNSC Army. This may be due to the fact that the Army is a land based fighting force, and thus none of the Army is assigned to naval battle ships, with the exception of transport by landing ships for planetary assaults.

The Army may be a land based garrison force. It is probably less efficient a fighting force than the Marines and might be used in a support or reserve role. It is also possible that the UNSC needed a faster, more expeditionary force like the Marines to hunt down elusive rebels and later, the Covenant. The Army might have subsequently been partially disbanded, with some units integrated into the Marine Corps. This may explain why some "leathernecks" (Marines) have been adressed in both the games and novels as simply "soldier."

Trivia

 * While no Army units have been identified, Tango Company might be one. Its members are referred to as soldiers, not Marines. Plus, its members show a very un-Marine like lack of discipline. However, until further information is revealed, it is assumed that Tango Company is a Marine unit.
 * The only known member of the UNSC Army is Colonel James Ackerson, an ONI officer who was once an infantryman. He is seen in an Army dress uniform.
 * A joke among members of the Halo community is that the UNSC actually has two Armies, Red and Blue. This is a reference to Red vs. Blue, a popular Halo machinima.