Can a cookie store information about me?

Not unless you provide the information! A web server is not allowed to access your files or hard drive; remember the rule: a web site can only access its own cookies.

A web server can use any information you explicitly provide to it, though. So if you fill out a form to provide your name, address, and telephone number, it can be captured and saved as a cookie.

So, are cookies good or bad?

Cookies are good for most users. Cookies allow a web site to store configuration information so that you don't have to enter it each time you visit their site. Examples are Yahoo Finance and The New York Times. Other sites require cookies so that they can keep track of information as you go from page to page. Many online shopping sites us this methodology.

If, however, you still prefer that no site be able to store any information, you can disable cookie storage via your browser's preferences.