To find out more about controlling and deleting cookies usage on your browser, visit the www.aboutcookies.org website.
SESS… is a Session cookie, the name is followed by a long random string. This is used for a user who is logged in so each page request can be matched to a users account (to display dynamic content and see if a user has permissions to see content).
System Specific cookies
__atuvc is used by the add this module (in the footer of the page for social networking links). it is used to track the source of a social link i.e. if a user clicks the add this button for Facebook, the cookie will tell Facebook where the source (the Croydon YPS website) came from.
Site usage cookies
The following are all used by Google analytics;
__utmz stores where a visitor came from (search engine, search keyword, link)
__utma stores each user’s amount of visits, and the time of the first visit, the previous visit, and the current visit (presumably partly for double checking of this information).
__utmb and __utmc are used to check approximately how long you stay on the site: when a visit starts, and approximately ends (c expires quickly).