Online search engines like Google only search with keywords, but when searching library catalogs and databases, you can search with either keywords or subjects.
|Pre-defined “controlled” vocabulary
|Not always intuitive
|Searches everywhere in a record or page
|Searches specific subject terms only
|Often yields irrelevant results
|Subheadings can help to focus results
|May not find all relevant results
|Results are usually very relevant to topic
Keyword searching is how we search most online sources like Google. While this usually results in a large set of results, a keyword search will also return anything that has your term or the string of characters anywhere in the record or page, frequently resulting in many irrelevant results.
Subject searching allows you to look for categories of information. When a library record for an item is created it is given at least one subject heading, usually several. These are based on a pre-defined (controlled) vocabulary so that all items about the same subject are organized and searchable together. While this usually gives a list of very relevant results, the words chosen as subject terms are not always intuitive or obvious.