Terms from DBpedia can be used to annotate Web content. Compared to other subject hierarchies, like the classic ones used within libraries, DBpedia has the advantage that each subject is backed by a rich description including abstracts in 14 languages. Another advantage compared to static hierarchies is that DBpedia evolves as Wikipedia changes.
One application that uses DBpedia terms for the annotation of Web content is DBpedia Spotlight. DBpedia Spotlight automatically detects mentions of DBpedia terms in textual documents, allowing you to create links from those documents to DBpedia. Another example is Faviki, a social bookmarking tool which allows you to tag Web pages you want to remember with Wikipedia terms. This means that everybody uses the same names for tags from the world's largest collection of knowledge.