1. A device for filtering information, comprising: first storing means for storing document data to be filtered; second storing means for storing fundamental document data for detecting at least one of newly created document and updated document; detecting means for detecting the at least one of newly created document and updated document among the document data stored in the first storage means based on the document data stored in the first storing means and the fundamental document data stored in the second storing means; similarity computing means for computing a similarity between the at least one of newly created document and updated document by detected the detecting means and a predetermined retrieval condition; and presenting means for presenting the at least one of newly created document and updated document detected by the detecting means according to the similarity computed by the similarity computing means.