Primary sources are produced at the time of the event or phenomenon you are investigating, and they purport to document it. They reflect what someone observed or believed about an event at the time it occurred or soon afterwards. These sources provide raw material that you will analyze and interpret. Primary sources can be published or unpublished. 

There are different types of primary sources for different historical periods. For example, church documents and saints' lives serve as primary sources for the study of medieval history, while newspapers, government reports, and photographs serve as primary sources for the modern period. Moreover, what constitutes a primary source depends in part on how you have formulated your research topic. An article in an academic journal from 1984 could be a secondary source because it is part of an ongoing scholarly analysis of your topic, or it could be primary source because it provides evidence of attitudes and opinions held by people in 1984. In other words, there is no intrinsic or distinguishing feature of a text or document that makes it a primary, rather than a secondary, source. 

Depending on your topic and your language skills, you may be looking mostly for translations of primary sources. For the most part, these will be available in books, often published many centuries after the period you are studying. One place to start looking for these is our guide to Primary Source Reprints. You can also search the Library Catalog: use the Advanced Search, and include the term "sources" as a subject. Limit your results to English.