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Search on Spock to find your friends, old acquaintances, your favorite celebrities, or people you would like to meet. With Spock you can discover people by searching for their name, or by using descriptive tags. For example if you type in "NFL Quarterback" into the search box, Spock will pull back a list of people who play quarterback in the National Football League.
Enter what you're reading or your whole library—it's an easy, library-quality catalog. LibraryThing also connects you with people who read the same things.
BibSonomy is a system for sharing bookmarks and lists of literature. When discovering a bookmark or a publication on the web, you can store it on our server. You can add tags to your entry to retrieve it more easily. This is very similar to the bookmarks/
The SCOT(Social Semantic Cloud Of Tags) ontology is to semantically represent the structure and semantics of a collection of tags and to represent social networks among users based on the tags.
A folksonomy is a user generated taxonomy used to categorize and retrieve Web pages, photographs, Web links and other web content using open ended labels called tags. Typically, folksonomies are Internet-based, but their use may occur in other contexts as
R. Jäschke, L. Marinho, A. Hotho, L. Schmidt-Thieme, und G. Stumme. Knowledge Discovery in Databases: PKDD 2007, 11th European Conference on Principles and Practice of Knowledge Discovery in Databases, Volume 4702 von Lecture Notes in Computer Science, Seite 506-514. Berlin, Heidelberg, Springer, (2007)