Social bookmarking is a method for internet users to store, organize, search and manage bookmarks of web pages on the internet with the help of metadata, typically in the form of tags that collectively and /or collaboratively become a folksonomy. Folksonomy is also called social tagging, “the process by which many users add metadata in the form of keywords to share content”. In a social bookmarking system, users save links to web pages that they want to remember and / or share. These bookmarks are usually public, and can be saved privately, shared only with specified people or groups, shared only inside certain networks, or another combination of public and private domains. The allowed people can usually view these bookmarks chronologically, by category or tags, or via a search engine. Most social bookmark services encourage users to organize their bookmarks with informal tags instead of the traditional browser-based system of folders, although some services feature categories/ folders or a combination of folders and tags. They also enable viewing bookmarks associated with a chosen tag and include information about the number of users who have bookmarked them. Some social bookmarking services also draw inferences from the relationship of tags to create clusters of tags or bookmarks. Many social bookmarking services provide web feeds for their lists of bookmarks, including lists organized by tags. This allows subscribers to become aware of new bookmarks as they are saved, shared and tagged by other users. As these services are matured and grown more popular, they have added extra features such as ratings and comments on bookmark, the ability to import and export bookmarks from browsers. With regard to creating a high-quality search engine, a social bookmarking system has several advantages over traditional automated resource location and classification software, such as search engine spiders. All tag-based classification of internet resources is done by human beings, who understand the content of resource, as opposed to software, which algorithmically attempts to determine the meaning of a resource. Also people can find and bookmark web pages that have not yet been noticed or indexed by web spiders. Additionally, a social bookmarking system can rank a resource based on how many times it has been bookmarked by users, which may be a more useful metric for end users than systems that rank resources based on the number of external links pointing to it. 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. Libraries have found social bookmarking to be useful as an easy way to provide lists of informative links to patrons. On the other hand social bookmarking possesses no standard for the structure of such tags (e.g. singular vs. plural, capitalization, etc.), mistagging due to spelling errors, tags that can have more than one meaning , unclear tags due to synonym/antonym confusion, unorthodox and personalized tag schemata from some users, and no mechanism for users to indicated hierarchical relationships between tags ( e.g., a site might be labeled as both cheese and cheddar, with no mechanism that might indicate the cheddar is refinement or sub class of cheese. Social bookmarking can also be susceptible to corruption and collusion. Due to it s popularity, some users have started considering it as a tool to use along with search engine optimization to make their website more visible. The more often a web page is submitted and tagged, the better chance it has of being found. 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.

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http://technorati.com
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http://www.propeller.com
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http://www.mixx.com
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http://www.kwoff.com
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http://www.socialbookmarkingsite.com
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http://www.onedepot.com
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http://www.olgn.net
http://www.nutmouth.com
http://www.mycartel.co.uk
http://www.mybookmarks.com
http://www.my-architecture.com
http://www.mvptimes.com
http://www.linxserver.com
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http://www.linkvote.com
http://www.kit-graphik.com
http://www.kez6.com
http://www.kaplunkit.com
http://www.kapely.net
to be continue...