At a basic level, it is analogous to a world map where the size of each country reflects population rather than area. The result could be considered a map of what the web community is thinking about. The altas is based on thousands of real queries which users typed into a popular search engine. The java applet at the bottom of the page transforms the resulting hierarchy into an interactive 2-D map, where each region's area is proportional to its popularity as a search target. You can drill down within a topic region for more detailed information on what we are all thinking about on that topic.
Gray rectangles are actual search queries.
Click on rectangles to see more detail. Hit backspace or click on title bar to zoom out.