A cadet is a young person training to become a military officer or learning leadership skills through a military-style program. At the United States Military Academy at West Point, cadets spend four years studying academics, practicing military drills, and developing the discipline and skills they'll need to lead soldiers. Similar academies exist for the Navy, Air Force, Coast Guard, and Marine Corps.

Many high schools and middle schools offer cadet programs where students wear uniforms, learn drill and ceremony, study leadership, and practice working as a team. These programs, like the Junior Reserve Officers' Training Corps (JROTC), help students build confidence, discipline, and responsibility. Being a cadet means learning to follow orders precisely, take care of your equipment, and work alongside others toward a common goal.

Today, cadet simply refers to someone in training for military service or participating in a youth program modeled on military structure. Police departments and fire departments also have cadet programs for teenagers interested in those careers.