Information filtering and information retrieval

Information filtering is a name used to describe a variety of processes involving the delivery of information to people who need it. Although this term is appearing quite often in popular and technical articles describing applications such as electronic mail, multimedia distributed systems, and electronic office documents, the distinction between filtering and related processes such as retrieval, routing, categorization, and extraction is often not dear. It is only by making that distinction, however, that the specific research issues associated with filtering can be identified and addressed.