This document discusses different types of information sources, including primary and secondary sources. It provides examples of primary sources like books, journal articles, photographs and patents, which are original works produced at the time without interpretation. Secondary sources are those that interpret and analyze primary sources, like biographies, review articles, textbooks and indexes. The document also discusses how to select the right information source depending on the topic, type of information needed and availability. It provides guidance on when to use different sources like books, encyclopedias, handbooks, journals, magazines, newspapers, databases and the internet.