As you conduct research when writing a paper, you will come across various sources of information. The various sources are typically classified as primary, secondary, or tertiary. Your teacher may require you to include each of these sources of information as the basis of your paper. A description of each type of information source is shown below. Examples are provided for each.

Primary Information Sources

A primary information source provides direct or firsthand information about an event, person, object, or work of art. Primary sources are contemporary to what they describe. They are original materials which have not been interpreted, condensed, or evaluated by a second party.

Here are some examples of primary information sources.

• Diaries
• Experiments
• Poems
• Personal correspondences
• Speeches
• Paintings
• Interviews
• Annual reports of an organization or agency
• Patents
• Court records

Secondary Information Sources

A secondary information source analyzes, interprets, or discusses information about a primary information source. Secondary sources are subsequent to what they describe, as they are produced at some point after a primary information source appears. Papers written by students typically contain mostly secondary sources.

Here are some examples of secondary information sources.

• Textbooks
• Biographies
• Magazine articles
• Book reviews
• Histories

Tertiary Information Sources

A tertiary information source lists, compiles, or indexes primary and secondary information sources. These sources are most often used to look up facts or to get a general idea about something.

Here are some examples of tertiary information sources.

• Almanacs
• Chronologies
• Directories
• Manuals
• Handbooks
• Guidebooks
• Indexes
• Statistics

The specific types of primary, secondary, and tertiary information sources you might use when writing a paper depends upon the subject of your paper. For example, if you were writing about the Civil War, you might use a Civil War soldier's diary as a primary source, a book about the Civil War as a secondary source, and a list of Civil War battle sites as a tertiary source.

Use these three types of information sources as needed when writing a paper.