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Keywords vs. Subject Headings

Keyword Searching

Keyword searching uses any words you can think of that best describe your topic. When entered into a search box, they will search across several fields in a database, for example the title, author, subject, and full text fields. A keyword search can be the first step on the way to finding subject headings appropriate to your topic and using them to get more relevant results.

Subject Searching

Subject searching uses subject headings that come from a predetermined list of possible terms and reflect the content of the item. Most academic libraries use Library of Congress Subject Headings (LCSH) for Subject Search of their online catalogs. A subject search is more specific than a keyword search: It looks in only one field of each record - the subject field. Many databases use subject headings that are unique to that particular database. This controlled vocabulary allows for consistency of terms across the database. These subject headings can be found in the database's thesaurus. In the thesaurus subjects are often listed with broader, narrower, or related subjects. Using the database's thesaurus will help you identify most effective search terms.

Research Tip

  • Start your search with keywords; use your own words that describe your topic best
  • Focus on the most relevant results and look at what subject headings have been added. In some databases subject headings can also be called "terms" or "descriptors.
  • Use those subject headings to further your search.

(Adapted from Oregon Tech Libraries)

What Are Primary Sources?

Primary sources are original materials that were created firsthand; they have not been run through the filter of interpretation. Often they are created during the time period that is being studied (correspondence, diaries, newspapers, government documents, art) but they can also be produced later by eyewitnesses or participants (memoirs, oral histories). You may find primary sources in their original format (usually in an archive) or reproduced in a variety of ways: books, microfilm, digital, etc.

Why Use Primary Sources:

Because primary sources are the documents or artifacts closest to the topic of investigation, they are a great way to gain insight into and an understanding of an event or topic.  You may find primary sources in their original format (usually in an archive) or reproduced in a variety of ways: books, microfilm, digital, etc. For example:

primary source wordle
  • Original Research (reported in journals & dissertations)
  • Diaries
  • Interviews (legal proceedings, personal, telephone, email)
  • Letters
  • Original Documents (i.e. birth certificate or a trial transcript)
  • Patents
  • Photographs
  • Proceedings of Meetings, Conferences and Symposia
  • Survey Research (such as market surveys and public opinion polls)
  • Works of Literature

What Are Secondary Sources?

secondary sourcesSecondary information is made up of accounts written after the fact with the benefit of hindsight. It is comprised of interpretations and evaluations of primary information. Secondary information is not evidence, but rather commentary on and discussion of evidence.

Examples include:

  • Biographies
  • Books
  • Commentaries
  • Dissertations
  • Indexes, Abstracts, Bibliographies (used to locate primary & secondary sources)
  • Journal Articles


Why Use Secondary Sources:

Because secondary sources are written with the benefit of hindsight and interpretation, they are useful at helping you understand your topic and seeing what scholars and other experts have to say about it.

Try adding these words to the end of your search to focus on primary sources:

  • sources
  • correspondence
  • personal narratives
  • photographs
  • diaries

For example: american revolution sources

(Adapted from Modesto Junior College)

Credible & Scholarly Sources of Information


Library Databases


  • MCC Library OneSearchSearch all of the MCC Libraries databases and catalog at one time. Use the limiters on the left side of the page to narrow results by full text, peer-review, format, date of publication, etc.

Select Websites

Make sure each and every source you plan on using in your paper or research assignment passes the CRAAP test.