Your are probably talking about "Drill Commands". Like "left face!" "Forward, March!" "Present Arms!" Or are you talking about the song-like rhyme that they repeat as they are marching? That's called a Cadence. Something like this: "Momma, momma, can't you see? Look what the Army's done to me. ... They took away my faded jeans; Now I'm wearing Army green. They took away my gin and rum; Now I'm up before the sun..."

Lucio, Maybe you are talking about bugle calls? Here are some of the camp calls played by the bugler: Reveille Assembly Drill Call Tattoo Taps In the days of the cavalry: To Arms Charge Retreat etc.