The European Union decided that it would be best if websites were to tell you that they are using cookies. This is important for many people who want to protect their freedom.
Unfortunately, without cookies many things cannot be achieved in a website. However, you may have a clear policy that spells out what you do with cookies (i.e. cook them, eat them, market them...) and that way people can decide to use your website further or not.
This is done by displaying a very clear pop-up, most often at the bottom of the screen, which gives the user a way to go to the page describing your cookie rules and a way to dismiss the message.
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