This column isn't about Oreos, Mrs. Fields, or Famous Amos.  But it is about cookies--magic cookies.  The mere mention of this technology in my last column sparked such loud, sometimes angry responses that a detailed discussion is clearly in order here.

Also known as persistent cookies, or just plain cookies, magic cookies aren't magic at all.  These files are essentially tokens of information, such as preferences and passwords, that Web servers collect from the clients that access them.  That data is then stored on your own hard disk--not on the server.  The next time you enter that site, the server looks for a file on your disk and reads the information you previously submitted.  Most leading browsers, including Netscape Navigator and Microsoft Internet Explorer, support cookies.  While having a remote site store data on your hard disk seems ominous, I'm unfazed by it.  Magic cookies aren't a threat to security.  In fact, they are often used in ways that can enhance your time on the Web.  Netscape uses cookies to let you access its new Personal Workspace area and also to save information about how you like your information presented.  For instance, I don't like Netscape's use of frames, and I turn off that feature when I visit the site's home page.  If you take a look, you'll see the information is benign.  The cookies.txt file is stored in the same folder as Netscape Navigator or Internet Explorer.  It's a text file, so you can easily view it.  In mine I can see that I've been to Netscape and that there are some statements in there about my preferences.  I can also see that I've been to SEARCH.COM and that my preferences are stored there, too.  When I visit my page at SEARCH.COM, I'm presented with my favorite search sites.

One smart use of cookie technology:  Web supermarkets.  Let's say my local supermarket is on the Web.  Cookies can store my selections as I browse the aisles.  As I choose a loaf of bread, a can of beans, and a six-pack (I eat well, don't I?) each item is stored in my cookies.txt file.  The store owner can erase that info from my file when I'm finished or keep it there for retrieval next time I shop.  That way he can greet me with a message such as, "Chris Barr, welcome back.  Don't miss today's special on whole-wheat bread."

If you're still not convinced about the security issue, bear in mind that each time you enter a site, your browser already tells the server a lot about you, such as which browser you're using and your IP address.  Take a look at BrowserWatch* to see what I mean.  And for sensitive data, Web masters can invoke a switch that requires a secure connection before it passes information.  If you're still worried, you can always delete the cookies.txt file after each session!