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Primary vs. Secondary vs. Tertiary Sources: Types of Sources

Three Types of Sources

In general, there are three types of resources or sources of information: primary, secondary, and tertiary.  It is important to understand these types and to know what type is appropriate for your coursework prior to searching for information.

  1. Primary sources: original materials on which other research is based.
    • original written works – speeches, poems, diaries, blogs, court records, interviews, surveys, letters, certificates of birth, death, or marriage, deeds, contracts, constitutions, laws, court records, tax records, census records, wills, inventories, treaties, report cards, medical records, passenger lists, passports, visas, naturalization papers, and military enlistment or discharge papers.
    • original research published in scholarly/academic journals.
  2. Secondary sources: materials that describe or analyze primary sources.
    • reference materials 
      • dictionaries, encyclopedias, textbooks.
    • books or articles that interpret, review, or synthesize original research/fieldwork.
  3. Tertiary sources: materials used to organize and locate secondary and primary sources.
    • Indexes – provide citations that fully identify a work with information such as author, titles of a book, article, and/or journal, publisher and publication date, volume and issue number and page numbers.
    • Abstracts – summarize the primary or secondary sources,
    • Databases – are online indexes that usually include abstracts for each primary or secondary resource, and may also include a digital copy of the resource.

(Mary Woodley, CSUN Oviatt Library)

Lets talk about primary sources

  • General Documents: Printed or written material relied upon to communicate, record, or prove something.
    • Strengths:  
      • Provides information on the who, what, where, when, why, and how of an event.
      • Provides written, printed, or graphic information.
      • Can clarify the purpose of the communication or transaction.
      • Can be a clue to the level of education of the author. 
      • Sometimes offers evidence of emotion.
      • Can stimulate the personal involvement of the reader.
    • Limitations: 
      •  Not a thoroughly objective source.
      • Generally a verbal, not a visual, record.
      • Often more to the story than what is presented.
      • Bias and agenda of the author to be considered.
      • Identity of the author often unclear (especially true in the case of government documents).
      • Author often no longer living and therefore unavailable to consult or verify.
      • Possibly difficult to read: handwriting difficult to decipher; words or phrases that are unfamiliar, their meaning changed over time.
      • Must be evaluated in conjunction with other evidence to determine whether the document presents information that is exceptional or conforming with previously established patterns.
  • Newspapers: A publication, usually issued daily or weekly, containing current news, editorials, feature articles, and advertising. 
    • Strengths: 
      • Many different types of information in one place: news articles, editorials, ads, columns, sports scores
      • Generally factual
      • Quick way to get basic info: who, where, when, what, why
      • Provides larger context of information
      • Written for a mass audience—easy to understand
      • Often has visual content: photographs, editorial cartoons, comics, ads
      • Addresses current events
      • Especially good for local information 
    • Limitations: 
      • Shows the bias of the publisher/owner, editor, writer
      • Subject to political and economic pressures
      • Fact checking not always thorough—written to meet deadlines
      • Newsprint is hard to preserve
      • Most newspapers not indexed; need to know dates to use
      • Varying ideas of what is considered newsworthy by locale and time
  • Advertisements:  Printed communication between seller/manufacturer and potential/ intended buyer/consumer; often with visual elements. 
    • Strengths: 
      • Visual element often primary
      • Widespread availability, familiar to us today
      • Record specific moments in time
      • Address human desire and aspirations on many levels
      • often include some information on manufacturer, manufacturing technology, product materials, content and use
      • Reflect prevailing social standards and values of the time
    • Limitations: 
      •  Often undated Creator of ad (writer, artist, ad agency) often unknown
      • Main function to sell; the information provided with that end in mind
      • Text entirely controlled by sponsor of ad
      • Often conveys prejudices and biases of the time (this can also be valuable to historians)
      • Often present a rosy, ideological view in which all problems are solved by the product Images possibly altered
      • Older ads containing contemporary references that are not obvious to a modern viewer Many segments of society are found in ads
    • Ask yourself: 
      • What are your first impressions?
      • What kind of document is it? How do you know?
      • Do you notice any unusual words or phrases?
      • Is there a date? If not, are there any other clues that might indicate when it was written?
      • Is there a location indicated?
      • Who wrote or created the document? How can you tell?
      • Who was the document written for? How do you know?
      • What is the purpose of the document?
      • Does the document convey a certain tone?
      • Does it imply anything without stating it directly?
      • Is the writer objective? Or are they bias?
  • Photographs: visual records obtained through photography
    • Strengths: 
      • Visual records of a moment in time
      • Convey many details about people, places, objects, and events
      • Convey information about everyday life and behavior that is best communicated in visual terms (hair and clothing styles, interior design) 
      • Sometimes provide evidence of attitude
      •  Important to the study of people who did not leave many written records 
      •  Can stimulate the personal involvement of the viewer
      • Do not require fluency in a particular language to understand
      •  Can be used to stimulate the memory of people
    • Limitations:
      •  Not a complete or objective source: the image that serves as the lasting record does not equate directly with the reality of the event itself
      •  Relationship of the photographer to those being photographed often difficult to determine
      • Reflect the bias or perspective of the photographer
      • People, place, date, and the name of the photographer are often not identified.
      •  The emotions and thoughts of those involved often are not evident.
      •  Information from this kind of source is often suggestive rather than definitive. Photographs must be studied in conjunction with other evidence. One must look at many photographs and/or other source materials such as documents and oral histories to determine if the information is unusual or part of a larger pattern.
  • Ask yourself: 
    • What are your first impressions?
    • What do you see in the photograph?
      • Make a list of people, objects, activities, buildings, or animals. 
    • What can you tell about the time period?
      • Any captions? a date? Location?
      • Names of people?
      • What kind of clothing is being worn? 
      • What time of year is it? Time of day? Why do you think so?
      • Where is the photography taken? Why do you think so?
    • If there are people in the photograph, what do you think their relationship is to one another?
    • What do you think happened right before and after the photograph was taken?
    • What questions do you have about the photograph?
  • Oral Histories: The record of an individual’s reminiscences, accounts, and interpretations of the past in his/her own spoken words obtained through planned interview(s) and preserved through the use of audio and video recordings, film, and/or written transcription.
    • Strengths: 
      • Personalize history by recording an individual’s remembrances (or opinions) about his/her life or an event in which he/she was involved
      • Provide information about a topic or time period that may otherwise lack documentation in written or archival records ✚ Often convey emotion clearly
      • Contain a story element appealing to students
      • Contain spontaneity and candor not always present in a personally written account
      • May contain unusual dialect or speech patterns
      • If the informant is living, they may be consulted for clarification or additional information.
    • Limitations: 
      • The fallible memory of the informant.
      • May include intentional or unintentional distortion of an event or one’s role in an event, thereby compromising the validit.
      • May contain inaccurate or incomplete record because of the informant’s reluctance to discuss certain topics.
      • The informant’s testimony may be inconsistent from one interview to the next.
      • May be influenced by the bias, goals, and/or the relationship of the interviewer to those being interviewed.
      • Interviewer’s questions may exert intentional or unintentional influence on the informant’s response.
      • May contain unfamiliar words or phrases from another time that are not clarified by the informant.
      • The bias of the historian/interviewer may become evident in the edited version of the interview(s), compromising the permanent record.
      • Oral histories are the mutual creation of the historian and the person being interviewed— the historian defines the topic or problem to be studied and the subject provides the information.
      • Always important to evaluate oral histories along with other evidence to determine whether they present information that is exceptional or conforms to previously established patterns.
    • Ask yourself: 
      • Who is speaking?
      • What people, places, and dates does the informant mention?
      • What topics is the informant discussing?
      • Does the informant reveal any emotions about these topics such as excitement, sadness, or happiness?
      • What kinds of words or phrases does the informant use? Are any of these unusual? Do they tell you anything about the informant’s character or history? 
      • What was the informant’s role in the events he or she describes?
      • How was the informant affected by the events he or she describes?
      • How does the informant and his or her unique story fit into the broader history you are studying?
      • How could information obtained from other primary sources reinforce the informant’s story? 
      • Does the informant mention any previously unknown aspects of the event that deserve further exploration?
  • Object:  an artifact and is something that has been produced or shaped by human workmanship.
    • Strengths: 
      •  Can offer clues when no written documents exist.
      • Can give insight into a people whose language the researcher cannot read or speak.
      • Can give clues as to the materials that were available during the time period.
      • Create a visual record through three dimensional facts: size, weight, texture.
      • Provide clues about function.
      • Convey info of everyday life.
      • Tell of ideas and information which either are not or cannot be expressed effectively in writing or speech (forms, colors, effects of visual arts; personal fantasies, idioms of taste, unspoken significance, customs, and prejudices).
    • Limitations: 
      • Do not usually give clues to the who, what, where, why, when, how of an event.
      • Do not always provide clues as to their designer and/or owner.
      • Cannot tell us about the frequency of their use.
      • Sometimes hard to tell the intended use.
      • Cannot know from a single type of object: 
        • how typical the object is of its time or of its type.
        • whether there are parts missing.
        • whether decoration is sparse or elaborate.
    • Ask yourself: 
      • ​First impressions?
      • What are its physical features?
        • made of?
        • Why was this material chosen?
        • Texture?
        • Color?
        • Can it be held? Heavy? Light?
        • Intact or broken?
        • Clean or dirty?
      • How was it constructed? Where? By whom?
      • What was its function? Practical or leisure use?
      • What type of person would have used the object? 
      • What type of person would have made the object?