Universal Wikipedia tags are often too long and too hard to enter and the exact name of a tag has to be known beforehand. Furthermore, tags are personal items – a private association to some concept.
Today’s conventional tagging mechanism, found on flickr, del.icio.us and youtube, allows users to associate web resources (i.e., documents, photos, videos and audios) with a set of keywords (i.e., tags). This mechanism works well for tagging resources that have a direct accessible URL. However, it falls short in being an effective tool for labeling the “deep” content of those resources — e.g., a partial clip from a youtube video.
The Calais web service automatically attaches rich semantic metadata to the content you submit. Using natural language processing, machine learning and other methods, Calais categorizes and links your document with entities (people, places, organizations,
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