It is a method for Internet users to store, organize, search, and manage bookmarks of web pages on the Internet .
These bookmarks are usually public, and can be saved privately, shared only with specified people or groups.
Most social bookmark services encourage users to organize their bookmarks with informal tags .
The concept of shared online bookmarks dates back to April 1996 .
They provided folders for organizing bookmarks, and some services automatically sorted bookmarks into folders .
Some included browser buttons for saving bookmarks and enabled users to email their bookmarks to others .
SOCIAL BOOKMARKING SITES
Del.icio.us uses a non-hierarchical keyword categorization system in which users can tag each of their bookmarks with a number of freely chosen keywords .
Del.icio.us has a "hotlist" on its home page and "popular" and "recent" pages, which help to make the website a conveyor of internet memes and trends.
All bookmarks posted to Del.icio.us are publicly viewable by default, although users can mark specific bookmarks as private .
Digg combines social bookmarking, blogging, and syndication with a form of non-hierarchical, democratic editorial control.
News stories and websites are submitted by users, and then promoted to the front page through a user-based ranking system.
Once a story has received enough "diggs", it appears on Digg's front page.
StumbleUpon is a web browser plugin that allows its users to discover and rate webpages .
StumbleUpon chooses which new webpage to display based on the user's ratings of previous pages .
Users can rate, or choose not to rate, any webpage with a thumbs up or thumbs down, and clicking the Stumble button .
For users, social bookmarking can be useful as a way to access a consolidated set of bookmarks from various computers, organize large numbers of bookmarks, and share bookmarks with contacts.
All classification of Internet resources is done by human beings, who understand the content of the resource.
Getting resources from others in our discipline.
Mistagging due to spelling errors and tags that can have more than one meaning .
Social bookmarking can also be susceptible to corruption and collusion.
Spammers have started bookmarking the same web page multiple times and/or tagging each page of their web site using a lot of popular tags, obliging developers to constantly adjust their security system to overcome abuses.