Mono audio refers to sound that is recorded and played back using one audio channel. This means that all the audio elements are combined into a single channel and played at the same volume, resulting in a flat, narrow, and less dynamic sound. Mono audio is often used in accessibility features for the hearing impaired, PA systems, AM broadcasting, and phone speakers. Stereo audio, on the other hand, is recorded and played back using two audio channels, which creates a more complex and immersive sound that is capable of producing the perception of width. Stereo systems are capable of creating the impression of sound source localization, which refers to the human ability to locate the position of a sound source within a space. Ultimately, whether to use mono or stereo audio depends on the preferences of the listener or the recording artist and the intended use of the audio.