--- title: Authorities and Controlled Vocabularies description: What each controlled vocabulary Preservated connects to is for — Nomenclature, Getty, Library of Congress, GeoNames, Wikidata, Iconclass — and which require attribution. section: reference order: 4 updated: 2026-06-19 verified: 2026-06-19 related: [guides/subjects-concepts-and-authorities, legal, reference/dates] features: [concepts-and-authorities] --- # Authorities and Controlled Vocabularies A reference for the published vocabularies Preservated can link your terms to: what each one covers, which fields it serves, and whether displaying its terms requires attribution. You never have to use any of these — [local terms](/docs/en-US/guides/subjects-concepts-and-authorities) work everywhere. Reach for an authority when you want terms that other institutions, aggregators, and search engines recognize. When a vocabulary requires credit, Preservated generates that credit automatically; see [Licenses and Attributions](/docs/en-US/legal). :::info Most vocabularies are looked up **live** from the provider as you type, with short-term caching, so authority search needs network access to that provider. A few high-volume vocabularies — **Nomenclature**, **TGM**, and **LCGFT** — are kept as a local copy that refreshes periodically, so they search faster and keep working even without network access to the provider. The terms you see are the same either way. ::: ## Object naming and classification ### Nomenclature for Museum Cataloging The object-naming standard for history, anthropology, and cultural-history museums — it names and classifies human-made objects by their original function. Best default for object names if you're not an art museum. - **Serves:** Object name, Classification. - **Attribution:** Required (CC BY 4.0). Home: ### Getty Art & Architecture Thesaurus (AAT) The art-world standard for typing objects and describing their physical make-up: object types, materials, techniques, styles, periods, and cultures. The default object-naming vocabulary for art museums, and the best source for materials and techniques regardless of collection type. - **Serves:** Object type, Material, Technique, Style/period, Culture, Genre/form, and topical subjects. - **Attribution:** Required (ODC-BY 1.0). Home: ## Subjects ### Library of Congress Subject Headings (LCSH) The general-purpose vocabulary for what an artifact is *about* — themes, events, and topics. The broadest, most widely recognized subject authority, and the default for general topical subjects. - **Serves:** Subjects, Events. - **Attribution:** Not required (US Government public domain); credit appreciated. Home: ### Thesaurus for Graphic Materials (TGM) The Library of Congress vocabulary built for indexing pictures — photographs, prints, and postcards — by subject and by photographic format. The recommended default subject vocabulary for image-heavy and photo collections, where it's finer-grained than LCSH. - **Serves:** Subjects, Genre/form (especially photographic formats). - **Attribution:** Not required (public domain); credit appreciated. Home: ### Iconclass A specialist classification for the iconographic subject matter of images — depicted themes, motifs, and narratives (a lion, a biblical scene, an allegory). Optional and advanced; useful for artwork and rich pictorial material. - **Serves:** Subjects (iconography). - **Attribution:** Not required (CC0); credit appreciated. Home: ## Genre and form ### Library of Congress Genre/Form Terms (LCGFT) What a resource *is* as a form or type at a discipline level — "Photographs", "Maps", "Documentary films". The general default for genre/form; pair with TGM for fine photographic formats or Getty AAT for art-domain granularity. - **Serves:** Genre/form. - **Attribution:** Not required (public domain); credit appreciated. Home: ## Creators and people > These vocabularies fill the **Creators** and **People** fields, not concepts, but they share the same authority picker — see [Working with Artifacts](/docs/en-US/guides/working-with-artifacts). ### Library of Congress Name Authority (LCNAF) Established names for persons, organizations, and meetings. The general-purpose authority for creators and depicted people. - **Serves:** Creators, People. - **Attribution:** Not required (public domain); credit appreciated. Home: ### Getty Union List of Artist Names (ULAN) Names of artists, makers, studios, and firms — richer than LCNAF for fine-art creators. Offered alongside LCNAF; prefer it for artists. - **Serves:** Creators (artists). - **Attribution:** Required (ODC-BY 1.0). Home: ## Places > These vocabularies fill the **Places** list, not concepts. Places carry map coordinates; an LCSH place that is an artifact's *subject* is recorded as a subject concept and cross-walked to a mappable place. ### GeoNames An open gazetteer of over eleven million place names with coordinates and feature types. The default for modern place lookup and anything that needs to appear on a map. - **Serves:** Places. - **Attribution:** Required (CC BY 4.0). Home: - **Note:** GeoNames requires a free username to be configured for your deployment; without it, place lookups against GeoNames return no results. ### Getty Thesaurus of Geographic Names (TGN) Current and historical places with types, dates, and coordinates. Preferred for historical and scholarly place authority; pair with GeoNames for modern coordinates. - **Serves:** Places. - **Attribution:** Required (ODC-BY 1.0). Home: ## Cross-domain ### Wikidata A collaborative knowledge base that links to nearly every specialist authority. Useful as a catch-all when a specialist vocabulary has no match, and as a bridge: picking a Wikidata item can carry over its linked Getty, Library of Congress, or GeoNames identifiers. - **Serves:** Any role, as a fallback and bridge. - **Attribution:** Not required (CC0); credit appreciated. Home: ## Local terms Terms your institution authors itself, for any role, with no external vocabulary or URI. Always available, never require an authority match, and carry no license. See [Subjects, Concepts, and Authorities](/docs/en-US/guides/subjects-concepts-and-authorities) for how to create one. ## Recorded by hand, not searched A few authorities can be stored on a term but have no live lookup, because their providers offer no reliable machine access: the **Getty Iconography Authority** (named iconographic subjects) and **VIAF** (a cross-walk hub for names). You can record a label and URI for these manually, but they won't appear in the authority search box.