Primary vs. Secondary Sources: Knowing the Difference

Defining the Sources

Primary Sources

These are immediate, first-hand accounts of a topic, from people who had a direct connection with it. Examples include:

• Diaries and letters
• Interviews and transcripts
• Original research data
• Official documents and legislation
• Artworks and literature

Secondary Sources

These are one step removed from primary sources. They cite, comment on, or build upon primary sources. Examples include:

• Academic textbooks
• Journal articles reviewing other research
• Biographies
• Literary criticism

When to Use Which?

In History, primary sources are your evidence (the 'what happened'). Secondary sources are the debate (the 'how we interpret it'). In Sciences, your lab results are primary; the textbook explaining the theory is secondary. A first-class essay will often analyze primary sources through the lens of secondary criticism.