They are necessary for the website to function and cannot be turned off. They are usually set in response to User’s actions which include a request for services, such as cookie settings, logging in or filling out forms.
They allow anonymous recording of visits and sources of traffic, which parts of the website are visited more or less often, the actions of the User on the website in order to measure and improve the efficiency of the website. They do not directly store personal data, but instead are based on the unique identification of the User’s browser and internet device.