Show Me The Cookies displays all current cookies your site is using. Once activated, you can find this list under Appearance - Cookies.
Furthermore you can display this list to your visitors by placing the shortcode [cookies] into any post or page.
WordPress uses several cookies under the hood by default. If you'd like to filter these out, you can use the shortcode [cookies-nowp]. If you like, you can replace the default separator between the cookie name and its value by adding your own string between the opening and closing shortcode tags, for example [cookies] ==> [\cookies].
This plugin is based on code by David Artiss, who kindly made it available on GitHub. I've wrapped it up into this standalone plugin.
To find out more about what cookies are and what can be done with them, please read
https://en.wikipedia.org/wiki/HTTP_cookie