A First Sergeant is a senior non-commissioned officer in the military, typically found in the United States Army and Marine Corps. This rank is responsible for the welfare, training, and discipline of soldiers within a company. The First Sergeant acts as a key advisor to the company commander and plays a crucial role in maintaining unit readiness. In the Army, the rank of First Sergeant is denoted by three chevrons and three rockers, often referred to as the E-8 rank. In the Marine Corps, the equivalent rank is also called First Sergeant, but it is represented by a different insignia. This position requires strong leadership skills and extensive experience in military operations.