You knew the library would have some info for you. According to NASA, “Just as the calendar you have on your kitchen wall does not cease to exist after December 31, the Mayan calendar does not cease to exist on December 21, 2012. This date is the end of the Mayan long-count period but then — just as your calendar begins again on January 1 — another long-count period begins for the Mayan calendar.”
For more from NASA on myths about the end of the world: http://www.nasa.gov/topics/earth/features/2012.html
Want to learn more about the Mayan calendar and their fascinating take on time? Listen to this podcast from CBC: http://www.cbc.ca/ideas/episodes/2012/12/17/the-end-of-days/.
(Thanks to the good folks at The M Word for the image!)