The four tone gong is a standard pause signal in many German schools, where an electronic chime replaced the older hand bell and corridor bell systems. Known as a Schulgong or Pausengong, it marks the start and end of lessons in a way every pupil learns to recognise within days. Recordings of the sound later spread online as ringtones, soundboard clips and prank sounds, because the tone is so distinctive that it works without any picture. It remains popular for school themed videos, classroom jokes and nostalgic edits.