We are now living Web 2.0 era. The term Web 2.0 has been introduced as a technical neologism in the web design field only a few years ago. However, it has all too soon become a social buzz word that has spread throughout many fields including the library community, business administration, marketing, etc.. It may be because of the distinct characteristics of Web 2.0 such as openness, anonymity and freedom of expression. In the era of Web 2.0, individual user is the key as "prosumers." Using Web 2.0 applications such as blogs, wikis, twitter and facebook, they can enjoy freedom of expression without any regulation. On the Web, everybody can be an information producer, consumer, critics and reporter by expressing his opinions and thoughts and share experiences directly without censorship. We also have the right to take, accept or criticize other people's opinions, experiences and thoughts. These intellectual accumulations constitute the collective intelligence of a community. Web 20. has been a great driving force of leading ordinary people to generate collective intelligence and participate in various social activities. 
    However, the freedom of expression combined with anonymity has also raised severe social problems. In terms of Web 2.0's negative impact, Andrew Keen argue thar Web 2.0 has created cult of digital narcissism and amateurism; which undermines the notion of expertise by allowing anybody to share and place undue social value upon their own opinions about any subject and post any kind of content, regardless of their knowledge level, credentials, or political biases. This digital narcissism is having an adverse effect not only on the online but also offline environment. There is no tolerance to people with different opinions. People show hostility towards differing opinions. There is also the moral hazard of making illicit use of other people's names; exemplified by digital witch-hunting. Malicious comments in Internet articles have led some people to commit suicide. Incorrect information of doubtful origin had ofter brought social disorder and corruption of the social system. One of the main reasons of this social phenomenon is the freedom of expression and anonymity of Web 2.0. Hiding behind Web 2.0, People have become digital anarchists who do not care about social convention or norms, who do not care about other people and who ignore moral standards. 
    There are many antiquated debates whether regulations are required to control this digital anarchy. Some insist that regulation is an infringement in freedom of expression and anonymity should be protected. Others argue the necessity of law and regulations protecting human rights from these digital hazards. In the end, Web 2.0 turns out to be two sides of the same coin: "digital democracy and digital anarchy" or "the protection of freedom of expression and the control of the freedom. "Beyond the tedious debates to tell right from wrong, it is time for self-introspection about when and how we use the two sides of web 2.0. 
    Web 2.0 is an outgrowth of technology with many positive impacts designed to improve our social life. But, we are gradually dominated by the technology that we design. Technology dose not transform society. Society develops technology to move a step towards social improvement. People who use the technology should understand what the technology should do for us. It should not control us. We should control it and utilize it properly. 
    We not have a tool with great potential. Web 2.0 can collaborate individual knowledge and establish collective intelligence to improve this society. In order to sully utilize it and to achieve positive society improvement from it, we should understand that the essence of Web 2.0 lies in mutual respect and considerations for others.

By    Lee Seung-min  
Professor of Library & Information Science