Skip to Main Content

Thesaurus for Graphic Materials I (TGM): An Introduction

The Thesaurus for Graphic Materials (TGM) is a tool for indexing visual materials by subject and genre/format. This is a guide for the usage of TGM I, subject indexing.

Introduction

The Thesaurus for Graphic Materials (TGM) is a tool for indexing visual materials by subject and genre/format. The thesaurus includes more than 7,500 subject terms to index topic shown or reflected in pictures, and 700 genre/format terms to index types of photographs, prints, design drawings, ephemera and other categories. New terms are added regularly. TGM is searchable through the Prints and Photographs Online Catalog (PPOC) and the Library's Linked Data Service.

This Guide is the new home for the Introduction to the Thesaurus of Graphic Material, which describes the rules and processes for integrating the TGM into visual material cataloging.

History of TGM

In 2007, the subject and genre/format vocabularies, previously maintained separately, were merged into a single list and migrated to new software, MultiTes. Although the thesaurus content remains essentially the same, there are some minor changes in field structure and labeling. For example, Public Note is now called Scope Note. Additionally, new fields were added to clarify term usage. For further information on these changes see "Fields in Term Record Displays" (via PPOC - About the Thesaurus).