Web 2.0 refers to new forms of online collaboration and sharing between internet users. Key aspects of Web 2.0 include blogs for sharing opinions; wikis for collaborative editing; social bookmarking and tagging to organize web pages; photo and video sharing sites; social networks; and RSS feeds to share updated information. Web 3.0 aims to take these interactive and personalized aspects even further through more complex personalization and relevance of online content and services.