| Keyword | Subject Term |
| Natural language | Pre-defined language or controlled vocabulary |
| Flexible | Precise |
| Searches all fields in database records | Searches one field in database records: SUBJECT |
| Results = too many with no context | Results = relevant and narrower pool of result |
| Search engine and database searching | Database searching only |
One method isn't better than the other. However they do produce different results. Keyword searching is a good starting point when researching an unfamiliar topic.
Subject headings, sometimes called descriptors, are a standardized way of describing the content of items within a database. These subject headings are pre-defined when works are added to a database. Items will have at least one subject heading, and many times multiple. Searching by a subject heading will limit the search results to items that share similar content, narrowing search results to a smaller set of retrieved records.
Search functionality limits subject searches to a single field within the record. The search term will likely appear in numerous other fields and within the text of the work.
Many databases provide a thesaurus, index, or subject list to aid in identifying Subject Headings applied to the specific database (e.g. arts and humanities indexes will be different from medical indexes). Searchers can also find the Subject Headings applied to an item by exploring the records retrieved in a search.
In EBSCOhost, for example, a list of Subjects will be included at the bottom of each entry in the retrieved search results list. In Nexis Uni, the list of Subjects will appear at the end of the individual retrieved document.
In EBSCOhost and other databases researchers can use a drop-down menu to make a search field a subject term specific field. The database search will be limited to that specific field.