Glossary of Library and Information Science - D

D

• descriptor - an index term used to identify a record in a database. It can consist of a word, phrase, or alphanumerical term. It can describe the content of the record or be an arbitrary code. When a descriptor is descriptive, it can be an effective search parameter.

• dissertation - a written treatise or thesis, usually lengthy, usually authored by a doctoral candidate, usually directed by a faculty advisor, and usually intended to advance the state of the art in a given discipline. There can be an oral component to the process, in which the dissertation must be defended in front of critical judges. Dissertation searches are valuable because of their currency.

• document delivery - the transfer of a database record, or other information resource, to the end user. It can involve direct internet or email transfers, CD delivery via mail, paper delivery via mail, or delivery via interlibrary loan.