English
Cookies are small files which are stored on a user's computer. The information the cookie contains is set by the server and it can be used by that server whenever the user visits the site. A cookie can be thought of as an internet user's identification card, which tell a web site when the user has returned.
This allows the server to deliver a page tailored to a particular user, or the page itself can contain some script which is aware of the data in the cookie and so is able to carry information from one visit to the website (or related site) to the next.
Cookies make the interaction between users and web sites faster and easier. Without cookies, it would be very difficult for a web site to allow a visitor to fill up a shopping cart or to remember the user's preferences or registration details for a future visit.
Web sites use cookies mainly because they save time and make the browsing experience more efficient and enjoyable. Web sites often use cookies for the purposes of collecting demographic information about their users.
Cookies enable web sites to monitor their users' web surfing habits and profile them for marketing purposes (for example, to find out which products or services they are interested in and send them targeted advertisements).
The time of expiry of a cookie can be set when the cookie is created. By default the cookie is destroyed when the current browser window is closed, but it can be made to persist for an arbitrary length of time after that.
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