Web 2.0 refers to second-generation web-based services that emphasize online collaboration and sharing among users. Examples include social networking sites like MySpace and blogs that allow people to post content and comment on each other's posts. Web 2.0 facilitates communication across geographic boundaries and transforms websites into platforms where users can add their own content and functionality. Key characteristics of Web 2.0 include users owning the data, encouraging contributions from users, and interactive interfaces that are easy for users.