Staff Sergeant is a rank of non-commissioned officer used in several countries.
The origin of the name is that they were part of the staff of a British army regiment and paid at that level rather than as a member of a battalion or company.
Staff Sergeant (SSG) is E-6 rank in the U.S. Army, just above Sergeant and below Sergeant First Class, and is a non-commissioned officer. Staff Sergeants are generally placed in charge of squads
Staff Sergeant (SSgt) is E-6 rank in the U.S. Marine Corps, just above Sergeant and below Gunnery Sergeant. A Marine staff sergeant is a staff non-commissioned officer rank.
Staff Sergeant (SSgt) is E-5 in the United States Air Force (U.S. Air Force). It ranks just above Senior Airman (SrA) and below Technical Sergeant (TSgt). It is the Air Force's first non-commissioned officer (NCO) rank, as well as the first Air Force rank to which promotion is attained on a competitive basis. SrA are considered for promotion if they attain that rank on or before February 1 of that testing year
Guy 2: " Yeah, he's an Ssgt."