Creative Commons licensed image by Flickr user wrestlingentropy
Important things to keep in mind:
This guide is NOT a comprehensive list of all existing primary sources, digital or otherwise. You will likely need to do some searching beyond this guide to find primary resources related to your specific topic. This guide is meant to help you learn how to search for primary sources.
Not every primary source will be available online or in digital form. Many sources are still available only in print, microform, or archival format.
Not every primary source will available in English. Keep this in mind especially when you are working on a world history topic. If you do not read other languages, you may have to frame your topic in ways that will justify using English-language sources.
(image from http://www.wordle.net/)
Primary sources are the raw materials of historical research - they are the documents or artifacts closest to the topic of investigation. Often they are created during the time period which 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.
Secondary sources are interpretations of events written after an examination of primary sources and usually other secondary sources, such as books and journal articles.
When you write a research paper, you are creating a secondary source!
The UC San Diego Social Sciences & Humanities Library created this 3 minute video to explain the difference between primary and secondary sources.
Here are some tutorials, created by librarians and historians, that offer tips on reading and writing history.