Site Structure, Search Engine, and Search Results 75 disease prevention to medical and public health professionals throughout the United States. ADP received much of its funding from NVIP but was inde- pendently operated and managed. ADP used its website as its prime channel for communicating information, educating professionals, and distributing materials, including posters, flyers, brochures, newsletters, handbooks, and articles designed for public health education. Sheila pointed to the top left center of the screen, adorned with hand- drawn images of popular cartoon characters from classic Superhero comics. "What I really hate is the graphics. These things take up space at the top, and the things people really want don't even appear unless you scroll way down--and even then you can't read them. I can't stand it!" Just one glance helped to explain Sheila's frustration. Only the scroll bar indicated that scrolling might be an important activity for a visitor. The visible part of the long page showed only a brief uninformative welcome message and was followed by swathes of white space. The long columns at either side mixed navigation links and text links, and the link labels were generic and uninformative. And these were just the problems that were immediately