1. A method of mapping contents to a low dimensional space, each of a plurality of items of contents having meta-information including classification information, comprising the steps of: assigning each item of contents a concept vector; and assigning each item of contents position information in a low dimensional space based on the concept vector assigned to the item of contents; wherein two items of contents are mapped at a short distance from each other to such an extent that the classification information of said one item of contents is close to the classification information of said other item of contents.