The idea of an online community goes back much rther than the 1990s, however. Very early forms of the Internet were used to foster social networks. The earliest online communities were dial-up bulletin-board systems (BBSes) such as The Well and numerous other regional systems. While these early communities did not have the features users have come to expect of modern social networking sites, they shared the core idea of connecting people with common interests.

Some of the earliest sites that we would recognize as being similar to todays social networking sites appeared in the mid 1990s, when the Internet started growing in popularity. These early sites focused on letting users reconnect with people they had known in the past, or finding out how they were connected to other site users.

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Reid Hoffman, LinkedIn founder and chairman, poses for a picture at the business networking companys headquarters in Mountain View, Social Networking Calif. See more pictures of popular web sites.

If youve updated your Facebook status, posted photos of last nights party to Flickr for your friends to see or made a business contact through LinkedIn, then youve used a social networking site. But what exactly is a social networking site? What are the key attributes that set it apart from other Web sites? How do they allow people to form online communities and share social networking information?

How Fantage WorksSocial networking sites like MySpace, Facebook and Twitter help teens and adults across the globe stay connected. But what about kids and tweens? What social networking options does the younger set have?

Friendster appeared in 2002 and followed a similar model,new york asian escort model but it offered additional features like photo sharing and it quickly became the first of the big social networking sites. Since then, however, Friendster has declined in popularity and is no longer one of the top 20 social networking sites in the United States [source: Hitwise]. After Friendster came MySpace and Facebook, along with sites like Bebo, Hi5, Orkut and Yahoo! 360. In addition, dozens of sites catering to very specific regions or tastes have sprung up. Whether youre interested in books, video games, music or meeting people from Denmark, theres probably a social networking site for you.

Grabianowski, Ed. What is a social networking site? 10 July 2009. HowStuffWorks.com. 04 July 2013.

How Online Social NetworksSocial Networking HowStuffWorks What is a social networking site? WorkOnline social networks are a great way to meet people and keep in touch with friends. Learn more about online social networks in this article.