A Pilot Ground Instructor is responsible for teaching ground school courses to student pilots, covering topics like aerodynamics, weather, navigation, and federal aviation regulations. They do not provide in-flight training but help students build the necessary theoretical knowledge for flight proficiency. Ground instructors typically work at flight schools, aviation academies, or within airline training programs. Certification is required from the FAA, with different levels such as Basic, Advanced, and Instrument Ground Instructor ratings.