A virtual community is a social network of individuals who interact through specific media, potentially crossing geographical and political boundaries in order to pursue mutual interests or goals. One of the most pervasive types of virtual community include social networking services, which consist of various online communities.
The term virtual community is attributed to the book of the same title by Howard Rheingold, published in 1993. The book, which could be considered a social enquiry, putting the research in the social sciences, discussed his adventures on The WELL and onward into a range of computer-mediated communication and social groups, broadening it to information science. The technologies included Usenet, MUDs (Multi-User Dungeon) and their derivatives MUSHes and MOOs, Internet Relay Chat (IRC), chat rooms and electronic mailing lists; the World Wide Web as we know it today was not yet used by many people. Rheingold pointed out the potential benefits for personal psychological well-being, as well as for society at large, of belonging to such a group.
These virtual communities all encourage interaction, sometimes focusing around a particular interest, or sometimes just to communicate. Quality virtual communities do both. They allow users to interact over a shared passion, whether it be through message boards, chat rooms, social networking sites, or virtual worlds. 
It's argued that online relations are not as valuable as offline ones because there is less socialization. Concerns with this kind of interaction also include verbal aggression and inhibitions, promotion of suicide and issues with privacy. Studies regarding the health effects of these communities did not show any negative effects, but that doesn't mean that there is no harm done. There was a high drop out rate of participants in the study that if continued could have led to a negative net effect. The health related effects are not clear because of the lack of thoroughness and the variation in studies done on the subject.
On civic participation
Online communities seem to have a direct impact on civic participation. 20.3% of members do something in real life at least once a year to support a cause related to their online community. 65% of members have started involvement in civic causes since they connected to the Internet. 43.7% are more involved with social activism since connecting with their online communities. Over half of virtual community members sign into their respective communities every day and 70% interact with other members daily.
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