This study compares production of archival descriptions with production of bibliographic records and use of user tagging systems. Archivists' descriptions indicate the subject matter of the collection in a similar manner as bibliographic records, but also indicate the collection's provenance, attribute significance to the materials, and give the history of the collection in the archive and outside it. Furthermore, I look at the structure of archival description in comparison to subject cataloging and user tagging. Adapting Tennis' 2006 framework, I look at Work Processes, Discourse, Structural Components and Descriptive Structures associated with these practices. By analyzing archival description under a common measure with concurrent descriptive practice, this work will fill a knowledge gap that will assist linking data by subject, describing materials on the web, integrating archival measures in future descriptive schemes.