With more than 120 million registered internet addresses (as of March 2007), the internet today symbolizes the largest information medium of our time. The internet grows daily with an overwhelming amount of information. This information is often stored in documents that use Hypertext Markup Language for formatting. Since the early 1990s, this system has proven effective, as it enables individual users to easily and efficiently annotate document contents with presentation instructions and publish them independently on the internet. These layout instructions can be easily interpreted by a computer program when accessing the corresponding resource and used to display the content, even though both the layout information and the actual document contents are in a textual format.