Web 2.0 refers to websites that stress user-generated content, simplicity of use, participatory culture, and interoperability (compatible with other goods, systems, and devices) for end users.
Darcy DiNucci originated the word in 1999, and Tim O'Reilly and Dale Dougherty popularised it at the inaugural Web 2.0 Conference in 2004. Although the term resembles the numbering of software versions, it does not denote a formal change in the nature of the World Wide Web. Rather, it describes a general shift that occurred during this time as interactive websites proliferated and began to eclipse the older, more static websites of the original Web.
A Web 2.0 website enables users to communicate and cooperate in a virtual community via social media discussion as producers of user-generated content. This contrasts with the original generation of Web 1.0 websites, when users were restricted to passively viewing material. Social networking service or social media sites (e.g., Facebook), blogs, wikis, folksonomies ("tagging" keywords on websites and links), video sharing sites (e.g., YouTube), image sharing sites (e.g., Flickr), hosted services, Web applications ("apps"), collaborative consumption platforms, and mashup applications are examples of Web 2.0 features.
Tim Berners-Lee, the creator of the World Wide Web, has questioned whether Web 2.0 is significantly different from previous Web technologies, calling the phrase jargon. His initial concept for the World Wide Web was "a collaborative medium, a place where we can all connect, read, and contribute." Berners-Lee, on the other hand, developed the phrase Semantic Web (also referred to as Web 3.0) to describe a web of material whose meaning can be interpreted by computers.