Just as sources can be scholarly or popular, sources can also be divided into primary and secondary. When evaluating sources, being able to determine whether it is primary or secondary is helpful as you continue in your research.
Primary Sources
A primary source is a firsthand or eyewitness account of information by an individual close to the topic. Examples of primary sources include autobiographies, personal correspondence (e.g., diary entries, letters), government documents, works of art and literature, statistics and data, and newspaper articles written by reporters close to the source. Today, even some social media posts are considered primary sources because they are firsthand accounts of information.
Secondary Sources
A secondary source is a source that is more removed from an event, usually written after the event has happened. Examples of secondary sources include biographies, interpretation of statistics and data, and anything written after an historical event or analyzing something that already happened (e.g., examining a work of art from 100 years ago).
What Should I Use?
Depending on your research, you may need more primary or secondary sources. For example, if you wanted to trace the history of whale sightings off the coast of Alaska, you would probably need to find some historical documents that provide firsthand information on whale sightings from a few hundred years ago. However, if you wanted to look at how boating has changed whale migration patterns, you would probably rely on some secondary sources that interpret data and statistics.