Skip to Main Content

Types of Sources

Ask a Librarian

Sorry, we are currently offline.

Information is created and shared in many formats, but how do we go from a current event to an entire book about that event? Understanding the progression of information will help you determine which type of source is most appropriate for your research. 

Information Cycle

Information Cycle:

The progression of coverage of a newsworthy event

The Day Of:

Social Media, TV, Radio, Web

  • Facebook
  • NPR
  • CNN
  • Twitter
  • ABCNews

The Week Of:

Newspapers, Web

  • New York Times
  • Salon
  • Green Bay Press-Gazette

The Week After:


  • Time
  • Newsweek
  • The Atlantic

Months After:

Academic Journals

  • Nature
  • The Journal of American History
  • Journal of Forensic Nursing

Year or More After:

Academic books, Government documents, Reference

  • Gender & Elections: Shaping the Future of American Politics by Susan J. Carroll and Richard L. Fox
  • Federal Student Loans, Education Could Improve Direct Loan Program Customer Service and Oversight: Report to Congressional Requesters by United States Government Accountability Office
  • Climate Change: An Encyclopedia of Science, Society, and Solutions by Bruce E. Johansen

Example: 9/11

Let's take a look at the information cycle for the September 11th attacks against the US. For a research project, you collect a variety of sources published from the moment the attacks occurred to the present. The first few sources were produced the day of and may contain inaccuracies due to the limited amount of information available at the time. As time progresses, the reliability of the sources increases because facts can be verified and new facts can be discovered.

**Note: the timeline does not contain all of the sources related to 9/11 due to the vast quantity of information available.

Timeline: 9/11 Information Cycle

9/11/01: 8:36am

  • Terrorists attack US WTC


  • Live News:
    • Records 2nd plane crashing into WTC


  • Website:
    • CNN report on events


  • Bush Address:
    • Address to nation aired live


  • Newspaper:
    • Milwaukee Journal Sentinel cover “Attacked”


  • Magazine:
    • Time cover shows towers burning

Spring 2002

  • Academic:
    • Article on racial profiling of Arabs post-9/11


  • Academic:
    • Article on psychological responses to 9/11


  • Academic Book:
    • Holy Terrors: Thinking about Religion after 9/11

July 2004

  • Government Report:
    • The 9/11 Commission Report


  • Website:
    • Washington Post: Remembering 9/11


  • Academic Book:
    • What Changed When Everything Changed


Copyright 2013 International Reading Association & NCTE. All rights reserved. ReadWriteThink materials may be reproduced for educational purposes.

Disclaimer: The content provided on this handout in no way reflects the opinions of ReadWriteThink or its supporting organizations: IRA, NCTE, or Verizon Thinkfinity.