1. A method implemented on a machine having at least one processor, storage, and a communication platform connected to a network for generating an abstract associated with a web page, comprising: obtaining a plurality of bookmarking tags collected via a bookmarking Web service associated with the web page from a database, the bookmarking Web service being configured to allow users to store bookmarks associated with the web page and share the bookmarks with other users; determining a subject matter associated with the web page based on the plurality of bookmarking tags; dividing textual content of the web page into a series of fragments each of which is associated with a topic that has a measure of similarity relative to the subject matter; selecting one or more fragments from the series of fragments of the web page, wherein the one or more fragments are associated with one or more topics, and the one or more topics have maximum measures of similarity relative to the subject matter; and generating the abstract associated with the web page from the selected one or more fragments of the web page.