What is a cookie ?
A cookie is a file deposited on the hard disk of the user’s computer when the latter browses a website through a browser (Chrome, Internet Explorer, Safari, Opera, Firefox). It is the server of the website that files this file.
Each cookie includes an anonymous identifier and contains information:
- name of the server that dropped it
- unique identifier
- expiration date
- used terminal (mobile, computer, tablet)
Usefulness of a cookie
The cookie has different functions such as being able to identify a user during several visits to a website. Some cookies also preserve the history of a shopping cart on an e-commerce site.
The advertising cookie makes it possible to display on advertising spaces an advertisement linked to the previous visits of a user. This same advertising cookie makes it possible to collect information on the course of the surfer or his centers of interests. The principle is similar for sharing buttons on social networks like Facebook, Twitter, Google Plus …
Good to know : a website can only read and write the cookies that belong to it.