Do you want people keeping lists of the Internet sites you visit regularly? That's exactly what happens when commercial Web sites upload "cookies" to your computer's hard drive.

Cookies are small data packets that contain information about your Web-surfing habits, which are then made available to cookie-savvy sites on the Internet.

The main use of cookies is to track demographics for advertising agencies that want to see just what kinds of consumers a certain site is attracting.

Some web sites also use cookies to keep your account information up-to-date. That way, when you enter a site where you have an account, Amazon.com for instance, the site knows immediately who you are and loads your personal preferences. This also how sites like Yahoo! offer "myYahoo!" personalisation features.

Companies like Double-Click and NetGravity use cookies to compile information about Web surfers, which in turn is used by advertising clients to deliver targeted ads. You can see a prime example of this strategy at the popular search engine Yahoo!, which displays a seemingly random banner ad when you first contact the site.

After you've entered a word search, for example "books for sale," the banner ad suddenly starts touting Amazon.com.

How can I stop them?

Is there a way to stop cookies? You bet! As long as you're using Microsoft Internet Explorer version 3.0 or later. IE gives you the option to display an alert when you receive a cookie from a site, and it allows you to reject the cookie.

Simply go to the View menu and select Options.... In the Options dialog box, click the Advanced tab. Scroll down the list box and deselect the Always Accept Cookies option. Then select Prompt before accepting cookies.

For IE 5.0, go the Tools menu and select Internet Options... Choose the Security tab and click on the Custom Level box. Scroll down to Cookies and change your options.

If you use Netscape, you can follow the same steps, only select Preferences under the Edit Menu, then select Advanced in the dialogue box that appears.

Disallowing cookies
When IE alerts you that a cookie is being downloaded, simply click the No button when it asks whether you want to accept it. Or, you can choose the Disable all cookie use and your browser will not accept any cookies...ever. The same is true in Netscape.

It's amazing how often IE will alert you to a potential cookie once you turn on the cookies alert option. In fact, the frequent alerts can be quite annoying, but at least you know when a site is hitting you up for information rather than having it all take place in the background.

What else can I do?

Besides turning on the cookies alert option, you can surf on over to the Electronic Frontier Foundation (EFF) page, join up, and sign petitions to try and stop advertising agencies from using cookies.

But for now, your best bet is to turn on the cookie alert option, set your browser for stun, and marvel at how many Internet Web sites are shills for Madison Avenue.

Are there any other options?
You can delete cookie files from your computer by initiating a hard drive search for any file with the word cookie in it.

You can drag those files into your Recycle Bin or Trash can. However, if you delete your cookie files, you may lose some settings, such as the passwords to sites you visit. In this case, IE will ask you to re-enter your password when you visit these sites. To prevent companies from placing new cookie files on your hardware, choose the option in your browser that asks for permission every time a cookie-planting attempt is made.

A more convenient approach is to install software that protects your cookie files. Macintosh users can download Cookie Cutter from Macdownload.com. Windows users can download Cookie Crusher from ZDNet's Software Library. Or you can go to www.anonymizer.com and have its Web site place itself between you and the sites you're visiting, keeping your privacy intact.

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