Colonel, a commissioned army, air force, or marine officer ranking above a lieutenant colonel and below a brigadier general. The comparable naval rank is captain. As insignia of rank a colonel in the U.S. armed forces wears a silver eagle on each shoulder. A colonel in the U.S. Army or Marine Corps normally commands a unit larger than a battalion but smaller than a division; an Air Force colonel commands a wing. A colonel may also hold a staff office.
Soldiers face danger every day -- detecting landmines, deactivating unexploded bombs and scoping out hostile buildings are tasks that don't always require a human presence. That's where military robots come in.
The T-34 Medium Tank had few amenities but enough power to help the Soviets beat back a Nazi invasion in World War II. This tank was well armored and heavily gunned, which made it the toughest tank the Germans encountered in Russia. Explore the T-34 Medium Tank.