This March 2015 article by Graeme Wood from The Atlantic is a powerful argument of definition.  Access it either through the permalink below or by accessing either your library databases or www.theatlantic.com

Be sure to get the full-color document with the images.

http://jccweb.sunyjefferson.edu:2055/login.aspx?direct=true&db=a9h&AN=100848076&site=ehost-live