A VOR, or VHF Omnidirectional Range, is a type of radio navigation system used by aircraft. It provides pilots with a way to determine their position and stay on course by receiving signals from ground-based stations. The VOR system operates in the VHF frequency range and allows for accurate navigation over long distances. VOR stations transmit signals that pilots can use to identify their location relative to the station. By tuning their aircraft's navigation equipment to the specific frequency of a VOR station, pilots can follow specific flight paths and ensure safe travel, especially in areas without visual landmarks.