I started the gCensus project for two reasons: First, the Census Department’s interface for mapping its data was clunky and looked like something out of the mid-90’s—hardly appropriate for a modern web service. Second, there was (and is) a wealth of geographic information publicly available, but few people have access to the kinds of tools needed to view it. Professional researchers investigating geographic data trends use programs known as GIS (Geographic Information Systems) packages for mapping. Unfortunately, there was no tool easily available to the average person who, say, wanted to see how family-friendly a neighborhood might be. gCensus is meant to fill that gap.





The obvious idea that comes up when thinking about web-based mapping and visualization is a Google Maps mash-up. In fact, such a site exists (and unfortunately, both I and the other site’s author picked the same gCensus name…). It turns out, though, that while Google Maps is great for some tasks, it’s not particularly good at visualizing quantitative data, as it doesn’t allow you to shade regions or otherwise present an intuitive view of the numbers.