Direction-finding, also known as radio direction finding (RDF), is a technique used to determine the direction of a radio signal. It is commonly used by navigators to locate their position and by radio operators to locate the source of a signal. The term 'NEMO' is an acronym for 'Non-directional Electronic Magnetic Orientation, ' which is a type of direction-finding system that uses a non-directional antenna to detect the direction of a signal.