The term Usenet Salute refers to the belief that one's post on an electronic bulletin board or similar system has been widely read despite the absence of evidence to support that belief. Posters on the Usenet groups did not receive feedback concerning how many people read their posts. If no one posted a response or sent an e-mail reply, they would not know if anyone had read it (unless they had access to server logs, which most would not). The term Usenet Salute refers to people who imagine that, despite the lack of responses, a great many people must have read their post but have simply chosen not to reply to it. The use of the term implies that the poster is deluding himself or herself.
A related phenomenon is captured in the phrase "The lurkers support me in e-mail," a reference to a poem written by Jo Walton.