This sound comes from Discord, the voice, chat and community platform that became especially widespread among gaming and creator communities in the late 2010s. The incoming call ringtone spread beyond the app because it is immediately recognizable and easy to loop in short edits. Online, people use it as a shorthand for being summoned to talk, interrupted mid-task or pulled into chaotic group conversations. Its staying power comes from how strongly it signals internet culture in just a second or two.