In Social networks everyone has their own social network (whether online or offline). Everyone has friends, families, and people they are acquainted with. An online social networking site simply makes our social networks visible to others who are not in our immediate network. So the single most important feature that distinguishes a social network from a community is how people are held together on these sites. In a social network, people are held together by pre-established interpersonal relationships, such as kinship, friendship, classmates, colleagues, business partners, etc. The connections are built one at a time (i.e. you connect directly with another user). The primary reason that people join a social networking site is to maintain old relationships and establish new ones to expand their network. Some obvious examples of social networks are Facebook, Myspace, and LinkedIn. One interesting feature about people’s social networks is that they are extremely unique. It is actually very difficult to fake a Facebook or LinkedIn profile, because your friends (or who you connect to) will collectively identify you.
Unlike social networks, communities (both online and offline) are more interesting from a social anthropological perspective, because they often consist of people from all walks of life that seem to have no relationship at all. Yet, as we’ve learned from history, communities are very robust social structures. So what is it that holds these communities together? Communities are held together by common interest. It may be a hobby, something the community members are passionate about, a common goal, a common project, or merely the preference for a similar lifestyle, geographical location, or profession. Clearly people join the community because they care about this common interest that glues the community members together. Some stay