Editing Document classification (section)

{{Short description|Process of categorizing documents}}

'''Document classification''' or '''document categorization''' is a problem in [[library science]], [[information science]] and [[computer science]]. The task is to assign a [[document]] to one or more [[Class (philosophy)|classes]] or [[Categorization|categories]]. This may be done "manually" (or "intellectually") or [[algorithmically]]. The intellectual classification of documents has mostly been the province of library science, while the algorithmic classification of documents is mainly in information science and computer science. The problems are overlapping, however, and there is therefore interdisciplinary research on document classification.

The documents to be classified may be texts, images, music, etc. Each kind of document possesses its special classification problems. When not otherwise specified, '''text classification''' is implied.

Documents may be classified according to their [[Subject (documents)|subjects]] or according to other attributes (such as document type, author, printing year etc.). In the rest of this article only subject classification is considered. There are two main philosophies of subject classification of documents: the content-based approach and the request-based approach.