The United Nations Space Command Marine Corps, normally shortened to UNSC Marine Corps or simply called Marines, is a branch of the United Nations Space Command Defence Force that is responsible for military operations conducted from the UNSC Navy. These military operations include land-based operations and the protection of Naval vessels and installations. Considered one of most highly trained military branches in the UNSC Defence Force and the Federal Republic, the Marine Corps is a rugged and diverse assortment of some of the best humans in the galaxy.