"It is important to know the number of times information has been synthesized or repackaged. Remember the children's game called 'Telephone?' ... [After the message is relayed through all of the children,] the final message and the original message frequently have very little in common. The more people the message passes through, the more garbled it is likely to become.
Unfortunately, this can also happen with more important information. When acquiring information, the researcher should be aware of the nature of the information, and if the information is not primary, should have some idea of how far it is from the primary source."
Teaching Information Literacy: 35 Practical, Standards-Based Exercises for College Students by Joanna M. Burkhardt, Mary C. MacDonald, and Andree J. Rathmemacher, p. 9.
Graphic "Urban Grapevine" by P.J. Crook from: Bridgeman Education
Primary sources can be
Secondary sources are works that
Secondary sources are generally magazines and other non-scholarly sources such as popular books. However, your textbook is a secondary source; it analyzes, evaluates, and interprets information in primary sources.