Tertiary sources organize, synthesize, or digest primary and secondary sources. Subject encyclopedias, Wikipedia, and textbooks are examples of tertiary sources.
Conducting background research can help you decide what to study, narrow your topic, or understand the context, vocabulary, or history behind your topic. You can connect your personal interest or current events to themes from your coursework, browse news sites or Wikipedia for background research, or find books that cover topics of interest to you. Subject encyclopedias and subject dictionaries are two helpful types of tertiary sources with passages describing topics within a subject area.