Cookies are probably the most misunderstood feature of computerdom. They are often depicted as menacing tools of surveillance. Many even show up in the results of spyware scans. But the truth is that cookies are not as powerful as they seem.

Cookies do not give direct access to your computer. Unlike viruses and spyware, cookies are not programs. They are inert text files that can't do much of anything. Some advertisers do abuse them. But, by and large, cookies do much more good than evil.

Cookies allow Web sites to be interactive. As text files, cookies provide the means for Web pages within the same site to pass notes to each other. Otherwise, any selections you make on one page are forgotten as soon as you click to another page.

Cookies are useful for shopping sites. A cookie can store a list of items you've selected to buy as you browse different product pages. Then the checkout page can read that list from the cookie. Another use for cookies is Web site customization. Cookies can be used to store your preferences for whenever you revisit a particular site.

Cookies usually do not carry information identifying a particular computer. You could transfer your cookies to another computer and use them just as well. They identify your computer to Web sites only as much as your car keys identify you to your car.