When you visit a website for the first time, you might see a banner pop up somewhere on the page, informing you that the website uses cookies. It usually explains that to continue using the website, you have to agree to the use of cookies. By clicking on “Accept,” this banner disappears. This is down to the first-party cookie, which was generated when the page was accessed. It stores the information that you have accepted the conditions. The banner won’t re-appear next time you visit this site.
Next, the website may ask you which language you prefer. This setting will also be stored in the cookie. If the website has a log-in area, you must register in order to use it fully. To do this, create an account with your e-mail address and a secret password that you will use to log in from now on. To facilitate this process, the cookie stores your e-mail address (but not your password). This means that when you next visit the site, you only need to enter your password because the site reads the e-mail address stored in the cookie.
The website has a large archive of information. To help you quickly find the pages you have visited, there is a small sidebar that links to the most recently visited subpages. This is also enabled by the cookie. Because all information in this example comes exclusively from this website, this text file is a first-party cookie. It is primarily intended to better your experience on the website. At the same time, the website operator receives valuable information on user behavior.
However, an unknown third party is still present: an advertising banner hosted by a third party has meanwhile placed its own cookie to store your usage data as well. This information is collected by a third party for web analytic purposes. From now on, they can follow your steps on the internet if you visit a site that has advertisements from this provider. Since this is from a third party, it is referred to as a third-party cookie. The website operator has never informed you about this nor asked for your consent.