Cookies are small pieces of data (text files) that are stored on the user’s hard drive by a web server as soon as the user visits a website. The file consists of a combination of letters and numbers that assign an identity to the user. If the user returns to the website, the cookie information is sent back to the server and the information on the user’s surfing behaviour can be read. Cookies can only be accessed by the user who set the cookie.


Cookies are used by shop and website operators to collect information a user provides through his behavior or active input on the website and to enable a personalized approach to the customer. Cookies enable, for example, the recognition of a user’s length of stay in the shop, the pages he has viewed and whether he is a returning visitor or not. In addition, the user’s personal settings can be saved to prevent the user from having to log on to the website each time. Cookies are also widely used in affiliate marketing as they enable the user to recognize the advertising medium from which the user came to the site and actually made a purchase.


There are two types of cookies: “session cookies” and “tracking cookies”. A session cookie is only stored for the duration of a session and is deleted again after the browser is closed. Tracking cookies are stored beyond a session of the user.


Third-Party Cookies vs. First-Party Cookies


A first-party cookie is set by the website operator and can only be accessed by him. A third-party cookie is set by a third party on a website – but can only be accessed by that third party. These cookies are mainly used for targeting. Third-party cookies can now be blocked by some web browsers by default.


Cookies do not store any personal data but process anonymous user profiles. Using the browser settings, users can decide if and which cookies they want to allow and which not. In order to comply with the data protection and privacy regulations, users must also give their permission for the website operator to use cookies (opt-in). This is usually queried through a cookie bar during the first page visit. The user also has the option of deleting his cookies at any time via the web browser.

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