an online advertising technique in which a page or email contains an image that is specifically tailored to your message. when the advertiser sees that your personal image has been requested by your computer, the advertiser knows you opened the page. then your email address becomes more valuable, because it's been confirmed as a real person.
the "increase cock size!!" spam had two web bugs in it, but I didn't see them because I don't use Microsoft Outlook
by claire danes July 05, 2003