A cookie (or computer cookie) is a small information sent by a website and stored in the user’s browser so that the website can consult the previous user activity. Its main functions are:
Cookies can be deleted, blocked or accepted as desired, so this should only be conveniently set up the web browser.
Cookies are commonly used by web servers to differentiate users and to act differently depending on these. One use of cookies is identified on a website. Users typically are identified by entering your credentials on a page validation; cookies allow the server to know that the user is already validated, and therefore may be allowed access services or perform operations that are restricted to unidentified users. Other sites use cookies to customize their appearance according to user preferences. Sites that require identification often offer this feature, but is also present in other that do not require. Customization includes presentation and functionality. Cookies are also used for tracking users through a website. The monitoring in one place is usually done with the intent to keep usage statistics, while tracking across sites typically aims to create anonymous user profiles by advertising companies, which are then used to guide campaigns advertising (deciding which advertising use) based on user profiles.