In these tweets, @replies are used to notify others that the people referenced are geographically proximate. In the tech scene, Twitter was presumed to be reciprocal, a true technology of the networked audience rather than a broadcast mechanism. As a result, it was considered proper to include someone in an @reply if they were in attendance at an event, or were part of an ongoing conversation. Re-tweets were attribution, so rebroadcasting someone’s tweet without crediting them was akin to plagiarism. People who continually tweeted without acknowledging anyone else, responding to @replies, or re-tweeting their friends were derided. Interaction designer Adrian Chan called these frequent references to others a way to delineate a tribe, a form of “social inclusion.”

Alice E. Marwick, Status Update, loc. 228