A cookie is a small file stored by a server in the terminal (computer, phone, etc.) of a user and associated with a web domain (that is to say in most cases all the pages of a website). This file is automatically returned in subsequent contacts with the same domain.
Cookies have multiple uses: they can be used to remember your customer ID with a merchant site, the current content of your shopping cart, the language of display of the web page, an identifier to track your browsing for statistical or advertising purposes, etc. Some of these uses are strictly necessary for the functionalities expressly requested by the user or for the establishment of the communication and therefore exempt from consent. Others, which do not meet these criteria, require consent from the user before reading or writing.
Source : CNIL
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