Definition: One of the ‘silent majority’ in an electronic forum; one who posts occasionally or not at all but is known to read the group's postings regularly. This term is not pejorative and indeed is casually used reflexively: “Oh, I'm just lurking.” Often used in the lurkers, the hypothetical audience for the group's flamage-emitting regulars. When a lurker speaks up for the first time, this is called delurking.
The creator of the popular science-fiction TV series Babylon 5 has ties to SF fandom and the hacker culture. In that series, the use of the term ‘lurker’ for a homeless or displaced person is a conscious reference to the jargon term.
The term dates back to the mid-1980s. Bulletin board systems (BBS) were often accessed by a single phone line (frequently in someone's home), there was an expectation that all who used a bulletin board would contribute to its content by uploading files and posting comments. Lurkers were viewed negatively, and might be barred from access by the sysop, if they did not contribute anything but kept the phone line tied up for extended periods.
By contrast, many modern Internet communities advise newbies to lurk for some time to get a feel for the specific culture and etiquette of the community, lest they make an inappropriate or redundant comment, ask a Frequently Asked Question, or incite a flame war. This leads to the tongue-in-cheek command to "lurk more", often intentionally misspelled as "lurk moar". The verb to "de-lurk" means to start contributing actively to a community having been a lurker previously. Lurking in terms of a forum makes sense because the forum is there to educate.
There are also some who lurk on a forum habitually, and rarely, if ever, contribute. It is generally difficult to guess how many such lurkers are present, due to their silence. In flame-wars, a participant who is losing an argument will sometimes claim to receive email support from lurkers. This inspired Jo Walton to write a folk song on the subject entitled "The Lurkers Support Me in Email".
Ethical implications of lurking:
Researchers who study online communities (e.g., (Lindemann 2005)) grapple with the potential negative implications of lurking. Specifically, the act of lurking, or “completely unobtrusive observation” (Garcia et al. 2009, p. 58) may allow individuals to gain an understanding into how individuals interact online by reading their posts or chats. However, if the researcher’s presence is detectable and individuals are able to see that someone is lurking rather than participating, they may feel that they are being spied on (Garcia et al. 2009). Additionally, ethical issues may be apparent if lurking researchers “harvest” (see Sharf, 1999) or take posts/entries featured in chatrooms/online journals without asking for the individual’s consent. As a result, individuals in online communities may feel that they are experiencing private interactions, but a lurker may see it as a public space for observation (Lindlof & Taylor, 2002)
* Online participation
* Parasitism (social offense)