The Web site may deliver one or more cookies to the client. The client stores cookie data in one or more files on its local hard drive. A cookie is a simple piece of text. It cannot be used as a virus, and it cannot access your hard drive. There has been a concern whether cookies can read information and gather sensitive information from a user's hard drive.
Cookies can only store data that is provided by the server or generated by an explicit user action.
Cookies can be used to store any information that the user volunteers. They cannot be used to gather sensitive information such as the fields in a preference file. If you still don't like cookies, you can set your browser to not accept them.