The Instrument Landing System (ILS) is a ground-based navigation aid that helps pilots land aircraft safely, especially in low visibility conditions. It provides precise guidance on the aircraft's position relative to the runway, using radio signals and a series of instruments in the cockpit. ILS consists of two main components: the Localizer, which guides the aircraft horizontally, and the Glideslope, which provides vertical guidance. Together, they ensure that pilots can approach and land on the runway accurately, even when weather conditions are poor, enhancing safety in aviation.