Web 2.0 is a platform which produce various service offered data from many people and it is activity open space depend on user focused community in diversity web environment. Web 2.0 is simple link structure with web site connectivity in informations such as page to page in other words, it is meaning of developing of semantical and circumstantial connection. The core of web 2.0 is user participation. RSS, Mash-up, UCC are main service of web 2.0 which make user directly participate from center of service offer to center of user manufactured an informations and then they offer re-information to other areas, also user freely express what they want through UCC and blogger. However, recently it comes the argument of skeptic of web 2.0 problem. Thus, In this research I will try to give an right comprehension and will try to have more accurate prediction of web 2.0 with the study of open service of web which is the key of web 2.0 success in a future.