What's the difference between a keyword and a subject heading?
When you use a search engine to find something on the web, you are usually using keyword searching. The keywords you choose to search for are usually the main concepts from the question you are hoping to answer.
Subject headings describe the content of an item using terms that are standardized across a database. Use subject headings to retrieve extremely relevant search results!
| Keywords | vs | Subject Headings |
| Natural language words describing your topic - a good place to start! | Pre-defined, controlled vocabulary, used to describe the content of each item (book, article, etc) in a database | |
| More flexible; can combine together in many ways | Less flexible; need to know the exact terms used | |
| Databases search keywords in all parts of each record; not necessarily connected together | Databases search subjects only in the subject heading or descriptor field | |
| May return too many or too few results | Allow you to focus your search very specifically | |
| May return many irrelevant results | Results usually very relevant to your research topic |
Source: http://cegep-heritage.libguides.com/content.php?pid=378455&sid=3099940
Scholars who need to do a thorough literature search on a topic are greatly assisted by a special kind of tool called a controlled vocabulary. Controlled vocabularies group synonymous words together under one main term: a Subject Heading. Searching with Subject Headings means researchers find articles that are about their topic, rather than articles that use specific words. In addition, many controlled vocabularies are arranged in a hierarchy or tree that shows the relationships between Subject Headings. This allows searchers to easily understand how their topic relates to others.
To find subject headings for your topic:
Another way to find subject headings:
Source: http://libguides.mit.edu/content.php?pid=36863&sid=271371
To select keywords to use for a search, start by writing your topic out as a sentence or question. For example:
"How are children impacted by explicit situations in the media?"
There are several aspects to this question. First, extract key terms from the topic question (bold). Then list synonymous or related terms for each - you have a list of keywords to use!
| Children | Affect | Violence | Media |
| Kids | Impact | Language | Video Games |
| Teens | Influence | Sex | Television |
| Adolescents | Consequence | Drug Use | Music |
Source: http://libraryschool.libguidescms.com/keywordsubject