Cookies and Spyware
Sunday, November 2, 2003

Both cookies and spyware can threaten your privacy online, but in different ways. Cookies are small text files, just a few dozen bytes' worth of numbers and letters, that Web sites deliver to a computer's hard drive. Many cookies merely store settings about how you use particular sites: A newspaper site such as washingtonpost.com, for instance, can use them to record which computers have registered to view news stories.

Other cookies, however, are used by Web advertising networks to track users' viewing habits across multiple Web sites, ensuring that they don't get repeat ads and, ideally, will see only those that match their interests. But these cookies can also be used, when combined with other marketing databases, to build detailed records of what you read and what you buy.

Fortunately, current Web browsers allow you to block third-party cookies -- far more practical than refusing all cookies. In Internet Explorer, for instance, click the Internet Options window's Privacy tab to adjust cookie settings.

Whatever cookie settings you use, Web sites still record such basic information as your computer's numerical Internet Protocol address. If that bothers you, you'll have to use a service that masks your address; Anonymizer.com, for instance, charges $30 a year for its Private Surfing service.

You can then turn your attention to a more serious risk -- one that drew little attention until recently.

Spyware is installed surreptitiously as an add-on to other programs, and tracks your computer use for the benefit of Web advertisers. It often displays ads but, like any mischievous application set loose in Windows, can do much worse -- potentially anything, including steal your confidential information or erase your hard drive. (Just about all spyware is Windows-only.)

But spyware can get on your computer only if you let it. Be skeptical about installing strange software -- read users' reviews at sites like Download.com (www.download.com). When you try a new program out, use its custom install option to see what sort of baggage it brings. (The lack of this option is a good reason not to load a program at all.) And if a strange Web site offers to install software for you, decline.

It's also a good idea to run a spyware-removal application such as AdAware (www.lavasoftusa.com) or Spybot Search and Destroy (www.safer-networking.org) on a regular basis to make sure nothing has sneaked onto your PC.

-- Rob Pegoraro



WPTech
© 2003 The Washington Post Company