Twitter (now X) cemented the modern arroba function in 2006. The @reply — e.g., @username — turned the symbol into a hyperlink, a direct line of public conversation. Facebook, Instagram, TikTok, and Discord followed. In every chat box, typing @ summons a drop-down list of contacts, servers, or roles.
As the internet expanded into bulletin board systems (BBS), IRC (Internet Relay Chat), AOL Instant Messenger (AIM), and early chat rooms, the arroba migrated from pure addressing into interaction. arroba chat