S, Anila2010-05-192010-05-192008-02-28978-81-902079-6-6http://hdl.handle.net/1944/1264The main feature of web 2.0 is its flexible interaction with users. It has been introduced ample of services where user is the central part. Collaborative tagging is also a product of Web 2.0 which can play an important role in the knowledge organization. Collaborative tagging is a new way to assign key words to internet resources by its users. This paper will give an overview to collaborative tagging, some tagging tools and some examples related to library fielenCollaborative TaggingSocial Book MarkingWeb 2.0Article