Social network sites are websites that allow a user to create a public self-profile and also maintain a list of other users in their social network. The user can usually view the profiles and social networks of others within the system. The sites usually provide a several ways for users to interact, such as chat, messaging, email, video, voice chat, file sharing, blogging, and discussion groups.
After joining a social network site, the user is asked to answer a series of personal questions. The user's online profile is generated from these answers which typically include descriptors such as age, location, interests, and an "about me" section. Most sites also encourage users to upload a profile photo. Some sites allow users to enhance their profiles by adding multimedia content or modifying their profile's look and feel. The visibility of a profile varies by site and according to user discretion. Users are prompted to identify others in the system with whom they have a relationship.
Wikipedia provides a list of over 100 social network websites, with MySpace and Facebook being the mostly widely used in 2007. MySpace, with over 100 million visitors, is very popular with teenagers, and Facebook, with over 70 million visitors, is popular with college students. Each social network site seems to focus on a specific target audience based on location, nationality, ethnicity, or interests. Some social network sites, e.g., LinkedIn and XING, are specifically aimed at professionals.
Click here for an interesting article on "Social Network Sites: Definition, History, and Scholarship" by danah m. boyd and Nicole B. Ellison.
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