explain DNA testing process

The Science: (Please use your text as a reference for this question). One day you are home visiting your grandmother and she asks you about an article she read that details a murder conviction based on DNA evidence yet she doesn’t really understand it. You’ve told her all about your exciting biology class so she’s very certain that you’ll be able to explain the process of DNA testing to her in a way she can understand.

1. How do you explain DNA testing in a way she will understand?
2. After your explanation your grandmother asks you how this procedure is different from other types of evidence like eye witness accounts or hair analysis. What do you say to her?

Assigned Textbook:

Mader, Sylvia S. (2015). Essentials of Biology, 4th ed. New York, NY: The McGraw-Hill Companies. ISBN 978-0-07-802422-1