Information flows in different ways in different subject areas. Each of the links below takes you to a timeline which will show you how information flowed from a sample event, research study, or artistic creation. Pick the subject area that you are researching or that you find interesting.

1. How is new information created?
2. How does it get from its source to you?
3. How does knowledge change over time?

Knowing how information flows helps you decide what type of information you need, whether it's a book, an article, a Web site, or a reference book. New information first appears in primary sources such as first-person accounts (newspapers, diaries, interviews), works of literature or art (novels, plays, paintings), or raw data (census numbers, economic statistics, surveys, experiments). Information from primary sources is analyzed and synthesized before being published in secondary sources such as encyclopedias, journal articles, and history books. Our understanding of events, data, or artwork evolves over time as secondary sources interpret — and re-interpret — the primary sources.