Known in Korean as haggyojong-sori, this bell is part of everyday school life in South Korea, played over speakers to announce the start and end of lessons, breaks, and exams. Its melodic electronic chime differs from a single ding sound effect or buzzer, which is why clips of it circulate on soundboards for Korean drama edits, study videos, and classroom memes. Creators reuse it as an instantly readable cue for school routines, discipline, and nostalgia, even for viewers who have never attended a Korean school.