The Library Catalog uses subjects or subject headings. These are similar to social media tags that describe what materials in the Catalog are about. The subjects may be useful as keywords or search terms to use in Catalog searches. Below are some examples of Catalog subject headings.
Food -- History
Food -- Social aspects -- History.
Food habits -- History
Gastronomy -- Social aspects -- History.
Plants, Edible -- History
Produce Trade -- History