Type 1 Cookies
Example: CMSSESSIDxxxxxxxx - a session cookie These cookies are essential in order to enable you to move around the website and use its features.
Type 2 Cookies
Examples: _pk_id.x.xxxx, _pk_ref.x.xxxx, _pk_ses.x.xxxx - Piwik analytics cookies These cookies collect information about how visitors use a website, for instance which pages visitors go to most often, and if they get error messages from web pages. These cookies don’t collect information that identifies a visitor. All information these cookies collect is aggregated and therefore anonymous. It is only used to improve how a website works.
The website AboutCookies.org explains how you can delete and control the cookies that are stored on your computer.