Difference Between Subject Terms and Keywords
It is important to know the difference between Subject Terms (also known as Subject Headings) and Keywords.
A keyword is simply an important word or short phrase describing an element of your research topic. Keywords can be a person's name, a place, an organization or a subject. Databases usually default to a keyword search. The database will look for your keywords anywhere in the item’s record including the title, author, publisher, abstract (summary), and subject fields. Using keywords is a great way to get your search started when you are first browsing and getting an idea of the material available to you. Searching with keywords has the effect of producing a lot of results, sometimes thousands or even millions if the keywords are not very specific and not combined with enough additional terms or limiters.
A Subject Term is different from a Keyword. A Subject Term is a tag added to each item in the database by librarians or the authors of the works. Subject Terms describe an item’s content and link it to similar sources. You will usually see them in the description of each item in the database, below its title.
How to Search by Subject Term
Using Subject Terms will often provide fewer results than a keyword search. You can search by Subject Term in two ways.
Because Subject Terms are not the same as keywords, you must know what a Subject Term is before you try to search with it. To find out what Subject Terms have been applied to your list of results, open the Subject drop-down on the left side-bar, then click Show More.
From there, you can click the Subject Terms that apply to your topic. Hit Count refers to the number of results in your list that have this Subject Term applied to it. When you cllick Update, the selected Subject Terms will be added to your search, and likely reduce the results.
Once you are familiar with Subject Terms that apply to your topic, you can use them to begin a new search. Change the Select a Field box to Subject Term and type the term in the corresponding search box.
How to Use Keywords and Subject Terms
Both keywords and subject terms can help you think of new ways to approach your research topic. It’s a good idea to peruse some of the keywords and subject terms listed in your results at the initial stages of your search. You might find that one of these terms improves your description of your topic, even if the particular article it's linked to isn’t exactly what you had in mind. Sometimes a new term might even be better than your original terms. You might even find some words that may no longer be in popular use, but were standard at one time (e.g. Great War for World War I) and may still be critical to uncovering important material. It can also be helpful to consult a thesaurus for additional help in brainstorming terms.
As you search and find new materials, keep track of the search combinations you use as well as relevant words and phrases that appear in titles, abstracts, or in the subject fields of books or articles. They can help you revise your search and hone in on the most relevant material.