Web 2.0 refers to a perceived or proposed generation of Internet-based services - such as social networking sites, wikis, communication tools, and folksonomies - that emphasize Internet-based sharing among users. Wikipedia
The continuously changing technologies of literacy mean that we must help children learn how to learn new technologies of literacy. In fact, the ability to learn continuously changing technologies for literacy may be a more critical target than learning any particular technology of literacy itself.
Donald J. Leu, Jr., The New Literacies