Google analytics cookies
Utmz Tracks where the visitor came from e.g. search engine or referring page or keyword. Utma Tracks each users number of visits, first visit, last visit. Utmb and Utmc Track when a visit starts and ends.
Most web browsers allow some control of most cookies through the browser settings. To find out more about cookies, including how to see what cookies have been set and how to manage and delete them, visit www.aboutcookies.org or www.allaboutcookies.org.
To opt out of being tracked by Google Analytics across all websites visit http://tools.google.com/dlpage/gaoptout.