Skip to Main Content

History of Science, Medicine, and Technology

What Are Primary Sources?

A primary source is "first-hand" information, sources as close as possible to the origin of the information or idea under study. Primary sources are contrasted with secondary sources, works that provide analysis, commentary, or criticism on the primary source. In literary studies, primary sources are often creative works, including poems, stories, novels, and so on. In historical studies, primary sources include written works, recordings, or other source of information from people who were participants or direct witnesses to the events in question. Examples of commonly used primary sources include government documents, memoirs, personal correspondence, oral histories, and contemporary newspaper accounts.

Where to Start: Primary Sources

Primary sources are often found in archives. Archives are a holding place for important historic materials. These materials can include legal documents, letters, diaries, ephemera, or even objects. There are archives held on UCLA's campus at UCLA Special Collections in YRL and at Special Collections in the Biomedical Library. To find out what items are in the holdings of an archive you need to search finding aids, which are guides to the collection. You can search the Online Archive of California for materials held in California, and through ArchiveGrid for materials held across the world. Remember, most archival collections are not digitized and you will need to visit the archive to see their holdings. Many archives will need advance notice to get the materials ready for you to view.

UCLA Digital Library

The links below are for relevant collections in UCLA's Digital Library. These items have all been digitized for you to view online.

Archives in California

The links below are to finding aids and websites of selected history of science archives in California. See note in Where to Start: Primary Sources (center column on this page) about searching for California-based special collections in the Online Archive of California.


These bibliographies are great sources to show what primary sources and archival materials are in existence.