When researching in a library, especially a research library, its catalog is probably the most important tool you will use, and one with which you should familiarize yourself as quickly as possible. Even if you think you have never used the Library Catalog here, you probably have and just do not realize it, since "Easy Search", the Library's federated search engine, sends all queries to the Library Catalog along with several other online research tools.

A library catalog is a database of records that identify and describe resources owned by the library. Most of these records describe published resources like books. Use the catalog to find both print sources and digitized sources in the Library's collections.

Why bother with subject headings in the online catalog when you can do keyword searching?

It’s true that you can find sources on a topic by doing keyword searches. But if you limit yourself to keyword searching, you are likely to miss important material on your topic that uses other terms. If you only need two or three books, you can probably find what you need by doing keyword searches, but if you are doing historical research, you can’t afford to miss critical material on your topic. For a comprehensive subject search, search with subject headings as well as keywords.

A good way to identify subject headings for a topic is to do a keyword search in the online catalog using terms you think describe the topic and try to identify a few relevant books. Look at the full record for those books to see what subject headings were used, then do another search on those headings.

As a rule of thumb, use fairly broad headings, as well as the specific ones that describe your topic, in order to make sure you haven't inadvertently eliminated relevant material that is contained within works of larger scope. Most likely you will find multiple headings to describe your topic, and you should use all of them. You can narrow your search in the online catalog by combining subject headings (as a phrase) with keywords, using the “Advanced Search” option.

Below are some subject headings that are relevant to this course. They are listed with the "official" punctuation, but note that you can leave out the punctuation when using these as search terms in the Library Catalog.

• Indochina -- History -- 1945-.
• Indochinese War, 1946-1954.
• Peace movements.
• Peace movements --United States.
• Peace movements --United States --History.
• Peace movements --United States --History --20th century.
• Presidents --United States --Election --1968.
• Protest movements.
• Protest movements --History.
• Protest movements --United States --History --20th century.
• Refugees -- Vietnam.
• Vietnam -- History -- 1945-1975.
• Vietnamese Americans.
• Vietnamese Conflict, 1961-1975.
• Vietnamese Conflict, 1961-1975 -- Chemical warfare.
• Vietnamese Conflict, 1961-1975 -- Personal narratives.
• Vietnamese Conflict, 1961-1975 --Protest movements.
• Vietnamese Conflict, 1961-1975 --Protest movements --Periodicals.
• Vietnamese Conflict, 1961-1975 --Protest movements --United States.
• Vietnam War, 1961-1975.
• Vietnam War, 1961-1975 -- Chemical warfare.
• Vietnam War, 1961-1975 --Protest movements.
• Vietnam War, 1961-1975 --Protest movements --United States.
• Watergate Affair, 1972-1974.
• Watergate Affair, 1972-1974 --Personal narratives.
• Watergate Affair, 1972-1974 --Press coverage.
• Watergate Affair, 1972-1974 --Public opinion.
• Watergate Affair, 1972-1974 --Sources.
• Watergate Trial, Washington, D.C., 1973.

In order to browse a menu of subject headings in the Library Catalog, you must use the Catalog's "Browse Search":

Like most documents, books can be either primary or secondary sources, depending on the nature of your research questions.

Any books published in the time period you are studying can be used as primary sources in principle. To find them in library catalogs and digitized book collections, combine a subject search with a search limit by date of publication.

Primary source documents, whether they were published or unpublished at the time, are often collected and published as books at a later time. To find these kinds of books (as described above), use one or more of the following Library of Congress subject terms in your search (or keep an eye out for them while browsing subject headings):

• correspondence
• sources
• diaries
• personal narratives
• interviews
• speeches
• documents
• archives
• early works to 1800

Biographies and autobiographies provide a window onto historical events as experienced by individuals. Autobiographies can be considered a type of primary source, since they often provide eye-witness accounts of events (bearing in mind that those accounts are often filtered through the later life experiences of the author).

To find biographies of individuals with connections to Vietnam, search the Library catalog using biography and Vietnam as subject terms:

After a new book is assigned subject headings, it is then “classified” according to one of three classification systems used in our Library: the Dewey Decimal Classification, the Library of Congress Classification, or Superintendent of Documents Classification ("SuDocs") for U.S. government publications (based on issuing agency).

In Dewey, the first three numbers indicate the main subject, and additional numbers are added after a decimal point to narrow the subject. Books and journals on historical topics are usually classified in the 900s, although much of social history gets classified in the 300s, and the history of science, technology, and medicine is classified in the 500s and 600s. Religion is classified in the 200s, philosophy in the 100s, literature and literary studies in the 800s, and the fine arts in the 700s.

For more detail on the Dewey Decimal classification consult this Guide to the Dewey Decimal System.

In the 1960s, many libraries adopted the Library of Congress Classification (LCC), but by that time the University of Illinois Library already had more than four million volumes classified in Dewey. We gradually began to transition to LCC. Today, many newer acquisitions, across all disciplines, are now being cataloged in LCC, resulting in a split collection.

Once you have identified a few books on your topic by doing a subject search in the online catalog, you can browse the shelf under the same general number(s) to find related works.

• For example, if you know that the book Watergate: The Presidential Scandal that Shook America has the call number 973.924 Oℓ86w2016, you could go to the Main Stacks to browse the shelves under the same Dewey number to find related material.
• Since our collections are split between Dewey and LCC, it's a good idea to find at least one book in each classification before you head to the stacks to browse!

Because so much of the Library collection is now stored in a high density, off-site storage facility, it's no longer possible to browse the collection as completely as it once was. You can, however, do "virtual shelf browsing" using the Library Catalog:

In addition to the 14 million+ printed books available to you here in the Library, we also have a rapidly growing collection of digitized books. You can find ebooks in the Library Catalog, just as you would find print books. Ebooks also tend to be aggregated into collections: