According to a piece of news (http://www.comscore.com/press/release.asp?press=2119 ), yahoo and Google’s are used by 135 millions and 128millions netizens each month. The findings show that they are one of netizens' favourite Internet tools. We like to use it and find the resources we need. Last December we have watched a programme called Google Deep Impact. It pointed out that some unheard search engine might trigger negative consequences. As the programme raise our interest in knowing more about the dark side of search engine. We decide to take it as the topic of our study.

In our website, we will describe what Search engine is, then we will introduce how a search engine works, also we will list the most popular search engines over the world. And we will also conduct an experiment to check that does search engine contain any problems. Finally we will analysis and discuss the problems of search engine.