From Joomla! Documentation
Cookies are small files that a website stores on you local computer to hold information about your interaction with the site. See [Cookie article in Wikipedia http://en.wikipedia.org/wiki/HTTP_cookie ]
Some Joomla extensions may create their own cookies.
Some possible methods are:
- Include a statement of cookie use in a site's terms of service.
- Use a custom html module to display information about cookies on each page of a site.
- If using the Remember Me option for login use the message field in the login module and login layout to inform visitors that this feature uses a cookie.