Library 2.0 is Libraries that use web 2.0, web 2.0 is mainly social media sites such as facebook, twitter, youtube etc.

Libraries use different web 2.0 features and sites for different purpose such as: Advertising on face book to build notoriety of the library and to advertise new and popular and improved features of the library specifically e-books, WI-FI and self check out loaning machines if that particular library has them.

Web 2.0 also allows Library personnel and personnel associated with libraries i.e.: government: finance etc. The web 2.0 specifically sites lie Facebook allow library personnel to communicate about features about the library and improves efficiency so that they can improve the library features quicker.