Cookies are small data files that store information relating to a website. For example, a cookie can be created to record the contents of a shopping cart, or to confirm that you are registered on the site on which you are browsing. When a cookie is created, events go like this:

• During the first contact, the website offers you a cookie for a specific domain. If you accept this cookie it is saved on the computer.

• Each time you contact this domain, the browser sends this cookie.

There is a reason for this rather abstract use: the cookie does not need to come from the website whose address is indicated in the address field.

For example, the website you visited may have an advertisement, in the form of an external image, and the site providing the image may send you a cookie. These so-called third-party cookies are often used for advertising purposes.

Cookies can be used to build a profile of your browsing habits, so there may be questions about their privacy.

If no expiration date is assigned to a cookie, it will expire at the end of the session, when you exit the browser. This kind of cookie is called a session cookie.