Cookies are pieces of information that a server can send to your PC, smartphone or tablet when you visit a website or use a social network. Then, the server that transmitted them can read and record the cookies that are on your PC, smartphone or tablet to get information of various type. Cookies have different functions: in many cases, they are useful because browsing is made easier and faster, as happens with technical cookies, used for example to save the language preferences or a shopping cart. In other cases, instead, cookies are used to monitor users while browsing; the so-called profiling cookies record information about what you buy or might want to buy, analyzing your readings, your hobbies, your travels, to customize the advertising that is shown to you when you open your e-mail or browse a social network. Then, there are third-party cookies, that are pieces of information recorded from sites other than those you visited and that are used for profiling purposes.