Web Bugs

Dan Gillmor reminded me of the existence of web bugs. Web bugs are (mostly) invisible images on a web-page, often only 1x1 pixel, that are used to track the loading of pages.

I wondered how you can see these in term of services. Each time a a page is loaded a record of the loading of such an image is stored somewhere. And these usage records can be analysed. In this sense it is a tracking service. The owner of the web-page might offer this service to another party, i.e. I open up my webpages and allow you to add web bugs, so you can see what users do. This sounds a bit silly. It is easier to sell your web log records. A webbug is only useful if it is combined with an asset in the web page, such as an advertisement. But then why not track the advertisements themselves? Well if you want to disconnect a specific advertisement from a more continuous profile of a user for instance. A web bug is also useful if you want to do independent tracking. [see the FAQ]

Thus a Web bug is the ingredient of a tracking service for publishers.