Online social networking is a 21st century phenomenon. Today, in the second decade of the century, internet service is widely available throughout the world and relatively affordable (even if someone doesn’t have his or her own computer, internet cafes are everywhere). This has made it possible for online social networking to become a central part of many people’s lives.

Though not the first service, Facebook is probably the most famous and most widely used of all the services. By July 2011, Facebook had more than 750 million active users. Facebook was launched in 2004 by Mark Zuckerberg and several of his college roommates and fellow students at Harvard University in the United States. The site allows “friends” to share what they’re doing at any single moment, play games, post photos, and wish each other Happy Birthday. For many people, it’s hard to imagine what life was like before Facebook.

But of course Facebook is not the only social networking site. A number of countries have developed their own sites, for example Vkontakte in Russia. By early 2011, Vkontakte had around 135 million accounts. The site was launched in 2006 by Pavel Durov, a graduate of St. Petersburg State University. Vkontakte is quite similar to Facebook but has one advantage: it uses a special technology allowing users to share larger files. Unfortunately, Vkontakte has had repeated problems with spam.

There is no doubt that social networking is here to stay. But not everyone agrees about its benefits to society. Academic researchers are now studying how these sites are influencing important areas of society, such as identity, privacy, youth culture and education. The technology continues to develop, with “real-time web” and GPS tracking making it possible to locate our friends, and be located, anytime, anywhere. Of course, this information may also become known to marketers and hackers.

Like anything, social networking can be used for either good or bad. Sadly, online bullying is relatively common (this is when one person spreads cruel or untrue stories about another person). But on a more positive note, social networking tools have played an important role in international political events. In the winter of 2011, young Egyptians used Facebook and other services to plan their protests and share news not only with each other, but with the world.