Quoting is one of the most powerful and unfamiliar features of Scheme. Andy Balaam explains what it is, and goes through an example of how you might use it. If you're new to Scheme, try http://youtu.be/byofGyW2L10 first. The slides for this video are here: http://www.artificialworlds.net/blog/2012/06/21/scheme-5-quotation-video/