A primary source is a reliable first-hand account of a topic or event usually created at or near the time the event occurred or the topic was relevant. There are many different types of primary sources, including:
On the other hand, a secondary source is an account created later by someone who did not personally experience the topic or event being discussed. In most cases, secondary resources are created by researching primary sources and then using that evidence to analyze and summarize the topic or event. Examples of secondary sources are:
A tertiary source summarizes and collects primary sources and secondary sources.
Examples of tertiary sources include: