Mr. K automatically turns on his computer as soon as he sits at his desk. Then he logs onto Messenger in order to chat with his friends and snoops around his friends' Cyworld mini-homepages. On his blog, he posts food images and writes his opinions about food he has eaten. He enjoys seeing the comments and trackbacks following his posts. Lately he is into 'following' on Twitter.    Mr. K is one of hundreds of PC users who use Social Networking Services (SNS) as part of their daily lives both on-campus and off-campus lives. SNSs are sites which aim to build online communities for people with similar interests.  Their relationships can be deep and sincere even if they are not familiar with each other. In fact, the use of such sites has already become a part of our lives although the term SNS has only come into general usage recently. Many people use these services as they offer the ability to instantly communicate and share information with friends and acquaintances at any time. These social networking sites are all web-based and include sites such as Cyworld, YouTube, My Space, Facebook and Twitter. The leading Korean networking site Cyworld, has passed its peak, but still has around 4,000,000 Koreans log in each day. In recent years, quite a number of Koreans have been using Twitter to create a new expression for a Twitter maniac, Twitterian.
 
How much have these social services affected society? Twitter has had world-wide repercussions leading up to the recent Iranian election through its role in spreading information which could not be reported by the mainstream media. People kept each other informed of news which had been suppressed by the government by transmitting it via SNS means. This had an affect on public opinion around the world making people more aware of the influence of social media. Through SNS we can feel a sense of belonging to one whole human family because social networking services transcend regional and national boundaries. Many people can interact about social issues and converse rather than feeling frustrated because of differences caused by distance.
 
Most sites are lightly regulated and people enjoy the outspokenness and boldness that they allow. Some people say there should be more restrictions on access to personal information however, and more accountability for writing opinions on SNS sites. A recent case in Korea showed how SNS sites can influence personal life. A singer's personal comments made 5 years ago were dispersed across the Internet by an unspecified person. Whether true or not they are, being made accessible on widely-read forums meant his opinions were broadcast far more than if they had been said in a face-to-face conversation. This kind of widespread availability can easily lead to   personal, political, social and cultural insecurities.
 
Homepages and blogs are another form of social media, but a characteristic of this social media, is its changeability with the popularity of specific media going through ups and downs. However, we do not need to feel any joy and sorrow in quick succession about this. It is obvious that types of media follow trends, but social experience is a basic aspect of society. We can be faithful to the basic properties of social media such as participation, openness, ease of communication and contact with others, but at the same time should keep in mind that we all need to take responsibility for its effects.