"So," you ask. "What is a Web Bug, and why say no?!" Glad you asked!
A Web Bug is a small invisible graphic on a Web page — or in an HTML-enabled e-mail message! — that is used to capture information on the person who is visiting the Web page. They usually consist of a graphics file that is one pixel high by one pixel wide (that's the size of the period at the end of this sentence!). Then it's set either transparent or the same color as the background, which makes it essentially invisible.
Note that a graphic file created in this manner often does have legitimate uses. For instance, this site uses a single-pixel transparent graphic file called SPACER.GIF, that is used, as the name implies, as a spacer between graphical elements on the page. By "stretching" it horizontally or vertically, I can add blank space between other elements on the page. For example, the code to create a 20-pixel vertical space looks like this:
<IMG SRC="pics/spacer.gif" Width=1 Height=20 BORDER=0>
But if this were a Web Bug, instead of the SRC="pics/spacer.gif", it would call for a file sourced on another server, such as SRC="http://www.servername.com/pics/spacer.gif", usually with a very different Web address than the site you're visiting.
So why are Web Bugs bad? While your computer is downloading the graphic file so it can "display" it (not knowing you'll never actually see it!), the server the file is being pulled from is capturing info on you such as the machine name and IP address of your computer, what browser you are using, etc. So why care if they are collecting this apparently anonymous info? Because the company that is paying the Web site to host their Web Bugs is also in cahoots with hundreds or thousands of other Web sites, and all it takes is for one of these sites — that offered to give you something in exchange for "registering" by giving them your personal information — to mate the anonymous info it captured via a Web bug with what you gave them, and now that very unique machine information is no longer anonymous! From then on, every time your machine shows up on any of the sites being monitored by that company, they know it's you! And by coupling Web Bugs with cookies that track what you do while you're there, and comparing them to other cookies dropped on you by other cooperating Web sites . . . well, you get the idea! Even worse, there is nothing to stop them from selling the data they are aggregating about you to other equally-unscrupulous companies! Nor is such rude behavior limited to commercial concerns: several US government agencies have already been caught collecting information on their Web site visitors!
So how can you fight this?
- Go to Bugnosis.org, set up by the Privacy Foundation, and download their free Bugnosis browser plug-in. It can be used to check every Web site you visit for Web Bugs!
- Visit the Privacy Foundation site and sign up for their newsletter, to keep up on Corporate America's ever-inventive methods for tricking you out of your personal information.
- Visit the Electronic Privacy Information Center and subscribe to their letter as well. Both organizations cover much of the same ground, but EPIC is much more active politically.