Since their introduction, social network sites (SNSs) such as MySpace, Facebook, Cyworld, and Bebo have attracted millions of users, many of whom have integrated these sites into their daily practices. As of this writing, there are hundreds of SNSs, with various technological affordances, supporting a wide range of interests and practices. While their key technological features are fairly consistent, the cultures that emerge around SNSs are varied. Most sites support the maintenance of pre-existing social networks, but others help strangers connect based on shared interests, political views, or activities.
Some sites cater to diverse audiences, while others attract people based on common language or shared racial, sexual, religious, or nationality-based identities. Sites also vary in the extent to which they incorporate new information and communication tools, such as mobile connectivity, blogging, and photo/video-sharing. Scholars from disparate fields have examined SNSs in order to understand the practices, implications, culture, and meaning of the sites, as well as users' engagement with them.
This special theme section of the Journal of Computer-Mediated Communication brings together a unique collection of articles that analyze a wide spectrum of social network sites using various methodological techniques, theoretical traditions, and analytic approaches. By collecting these articles in this issue, our goal is to showcase some of the interdisciplinary scholarship around these sites. The purpose of this introduction is to provide a conceptual, historical, and scholarly context or the articles in this collection. We begin by defining what constitutes a social network site and then present one perspective on the historical development of SNSs, drawing from personal interviews and public accounts of sites and their changes over time. Following this, we review recent scholarship on SNSs and attempt to contextualize and highlight key works. We conclude with a description of the articles included in this special section and suggestions for future research. Social Network Sites: A Definition
We define social network sites as web-based services that allow individuals to (1) construct a public or semi-public profile within a bounded system, (2) articulate a list of other users with whom they share a connection, and (3) view and traverse their list of connections and those made by others within the system. The nature and nomenclature of these connections may vary from site to site. While we use the term "social network site" to describe this phenomenon, the term "social networking sites" also appears in public discourse, and the two terms are often used interchangeably.
We chose not to employ the term "networking" for two reasons: emphasis and scope. "Networking" emphasizes relationship initiation, often between strangers. While networking is possible on these sites, it is not the primary practice on many of them, nor is it what differentiates them from other forms of computer-mediated communication (CMC). What makes social network sites unique is not that they allow individuals to meet strangers, but rather that they enable users to articulate and make visible their social networks.
This can result in connections between individuals that would not otherwise be made, but that is often not the goal, and these meetings are frequently between "latent ties" (Haythornthwaite, 2005) who share some offline connection. On many of the large SNSs, participants are not necessarily "networking" or looking to meet new people; instead, they are primarily communicating with people who are already a part of their extended social network. To emphasize this articulated social network as a critical organizing feature of these sites, we label them "social network sites. While SNSs have implemented a wide variety of technical features, their backbone consists of visible profiles that display an articulated list of Friends1 who are also users of the system. Profiles are unique pages where one can "type oneself into being" (Sunden, 2003, p. 3). After joining an SNS, an individual is asked to fill out forms containing a series of questions. The profile is generated using the answers to these questions, 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. Others, such as Facebook, allow users to add modules ("Applications") that enhance their profile. The visibility of a profile varies by site and according to user discretion. By default, profiles on Friendster and Tribe. net are crawled by search engines, making them visible to anyone, regardless of whether or not the viewer has an account. Alternatively, LinkedIn controls what a viewer may see based on whether she or he has a paid account.
Sites like MySpace allow users to choose whether they want their profile to be public or "Friends only. " Facebook takes a different approach—by default, users who are part of the same "network" can view each other's profiles, unless a profile owner has decided to deny permission to those in their network. Structural variations around visibility and access are one of the primary ways that SNSs differentiate themselves from each other. After joining a social network site, users are prompted to identify others in the system with whom they have a relationship.
The label for these relationships differs depending on the site—popular terms include "Friends," "Contacts," and "Fans. " Most SNSs require bi-directional confirmation for Friendship, but some do not. These one-directional ties are sometimes labeled as "Fans" or "Followers," but many sites call these Friends as well. The term "Friends" can be misleading, because the connection does not necessarily mean friendship in the everyday vernacular sense, and the reasons people connect are varied (boyd, 2006a). The public display of connections is a crucial component of SNSs.
The Friends list contains links to each Friend's profile, enabling viewers to traverse the network graph by clicking through the Friends lists. On most sites, the list of Friends is visible to anyone who is permitted to view the profile, although there are exceptions. For instance, some MySpace users have hacked their profiles to hide the Friends display, and LinkedIn allows users to opt out of displaying their network. Most SNSs also provide a mechanism for users to leave messages on their Friends' profiles. This feature typically involves leaving "comments," although sites employ various labels for this feature.
In addition, SNSs often have a private messaging feature similar to webmail. While both private messages and comments are popular on most of the major SNSs, they are not universally available. Not all social network sites began as such. QQ started as a Chinese instant messaging service, LunarStorm as a community site, Cyworld as a Korean discussion forum tool, and Skyrock (formerly Skyblog) was a French blogging service before adding SNS features. Classmates. com, a directory of school affiliates launched in 1995, began supporting articulated lists of Friends after SNSs became popular.
AsianAvenue, MiGente, and BlackPlanet were early popular ethnic community sites with limited Friends functionality before re-launching in 2005-2006 with SNS features and structure. Beyond profiles, Friends, comments, and private messaging, SNSs vary greatly in their features and user base. Some have photo-sharing or video-sharing capabilities; others have built-in blogging and instant messaging technology. There are mobile-specific SNSs (e. g. , Dodgeball), but some web-based SNSs also support limited mobile interactions (e. g. , Facebook, MySpace, and Cyworld).
Many SNSs target people from specific geographical regions or linguistic groups, although this does not always determine the site's constituency. Orkut, for example, was launched in the United States with an English-only interface, but Portuguese-speaking Brazilians quickly became the dominant user group (Kopytoff, 2004). Some sites are designed with specific ethnic, religious, sexual orientation, political, or other identity-driven categories in mind. There are even SNSs for dogs (Dogster) and cats (Catster), although their owners must manage their profiles.
While SNSs are often designed to be widely accessible, many attract homogeneous populations initially, so it is not uncommon to find groups using sites to segregate themselves by nationality, age, educational level, or other factors that typically segment society (Hargittai, this issue), even if that was not the intention of the designers. A History of Social Network Sites The Early Years According to the definition above, the first recognizable social network site launched in 1997. SixDegrees. com allowed users to create profiles, list their Friends and, beginning in 1998, surf the Friends lists.
Each of these features existed in some form before SixDegrees, of course. Profiles existed on most major dating sites and many community sites. AIM and ICQ buddy lists supported lists of Friends, although those Friends were not visible to others. Classmates. com allowed people to affiliate with their high school or college and surf the network for others who were also affiliated, but users could not create profiles or list Friends until years later. SixDegrees was the first to combine these features. SixDegrees promoted itself as a tool to help people connect with and send messages to others.
While SixDegrees attracted millions of users, it failed to become a sustainable business and, in 2000, the service closed. Looking back, its founder believes that SixDegrees was simply ahead of its time (A. Weinreich, personal communication, July 11, 2007). While people were already flocking to the Internet, most did not have extended networks of friends who were online. Early adopters complained that there was little to do after accepting Friend requests, and most users were not interested in meeting strangers.
From 1997 to 2001, a number of community tools began supporting various combinations of profiles and publicly articulated Friends. AsianAvenue, BlackPlanet, and MiGente allowed users to create personal, professional, and dating profiles—users could identify Friends on their personal profiles without seeking approval for those connections (O. Wasow, personal communication, August 16, 2007). Likewise, shortly after its launch in 1999, LiveJournal listed one-directional connections on user pages. LiveJournal's creator suspects that he fashioned these Friends after instant messaging buddy lists (B.
Fitzpatrick, personal communication, June 15, 2007)—on LiveJournal, people mark others as Friends to follow their journals and manage privacy settings. The Korean virtual worlds site Cyworld was started in 1999 and added SNS features in 2001, independent of these other sites (see Kim & Yun, this issue). Likewise, when the Swedish web community LunarStorm refashioned itself as an SNS in 2000, it contained Friends lists, guestbooks, and diary pages (D. Skog, personal communication, September 24, 2007). The next wave of SNSs began when Ryze. com was launched in 2001 to elp people leverage their business networks. Ryze's founder reports that he first introduced the site to his friends—primarily members of the San Francisco business and technology community, including the entrepreneurs and investors behind many future SNSs (A. Scott, personal communication, June 14, 2007). In particular, the people behind Ryze, Tribe. net, LinkedIn, and Friendster were tightly entwined personally and professionally. They believed that they could support each other without competing (Festa, 2003). In the end, Ryze never acquired mass popularity, Tribe. et grew to attract a passionate niche user base, LinkedIn became a powerful business service, and Friendster became the most significant, if only as "one of the biggest disappointments in Internet history" (Chafkin, 2007, p. 1). Figure 1. Timeline of the launch dates of many major SNSs and dates when community sites re-launched with SNS features Like any brief history of a major phenomenon, ours is necessarily incomplete. In the following section we discuss Friendster, MySpace, and Facebook, three key SNSs that shaped the business, cultural, and research landscape. ttp://jcmc. indiana. edu/vol13/issue1/boyd. ellison. html Content Pros Of The Social Networking Sites •The best advantage of social networking sites is that these sites allow you to keep in touch with your friends, classmates, and relatives. It is also the most cost effective way to keep in touch with your people. Here geographical locations are no barrier to stay in touch. •These sites allow you to send and receive messages, upload photos, and videos. As such, they are very interactive as you can get to see what your friends and relatives are up to. With social networking sites, you are not bound by any geographical and cultural differences. You get to meet and know a variety of people whose interests are similar to your own. These sites are a window to different cultures and places. •You can build a network of contacts and interact with a lot of people at the same time. As such, you can spread your thoughts and interests to a large number of people. •The social networking sites also facilitate you to procure information on any subjects from anywhere. These sites also make it easier and faster to collect the information. Social networking sites can also be a tool to promote your business, services, products, or websites. Due to the huge number of people who regularly use networking sites it has found huge favors among advertisers. http://wiki. answers. com/Q/What_are_the_advantages_and_disadvantages_of_social_networking The Cons Of Social Networking Sites •The most glaring disadvantage of social networking sites is the risk of identity theft and fraud. The personal information of users can be used by dubious people for illegal activities. Information like the e-mail address, name, location, and age can be used to commit online crimes. Also, many people pretend to be someone else and prepare their online profiles with false information, so as to dupe unsuspecting users. So, if you do not know the person face to face then it will be very hard for you to find the real identity. •Another cause of concern is cases of online harassment and stalking. Since the social networking sites, are very poorly regulated so it can be a very fertile ground for people trying to get even with you. They can spread malicious humor among your friends and also download and morph your photos. http://wiki. answers. com/Q/What_are_the_advantages_and_disadvantages_of_social_networking