Cookies are a general mechanism which Web servers can use to both store and retrieve information on the browser. If one exists, it presents it to Netscape when accessing the Web site. The Web server at Netscape examines the cookie information and it serves up content back to your browser based on what is in the cookie. It also writes another cookie into your cookie file. Although in this case it is the Netscape server that is writing to the cookie file in your hard drive, there is no need to fear about a virus infecting your cookies.
Cookies are safe.
Cookies are a good thing in that they provide a way of remembering who you are, where you have been, and what are your preferences. Cookies allow many types of applications to become Web-enabled. Shopping applications can now store information about the currently selected items. For fee services can send back registration information and save you from retyping in a user name on your next visit. However, you might feel uncomfortable about Web sites having information about you.