The atlas presents a snapshot in time. While giving an impression of the way things are, it actually peers into a dynamic industrial system. Some aspects are changing quickly, while others have looked similar for decades. The atlas provides a baseline of information that potentially can be repeated in the future to analyze trends among districts and types of sites.

The atlas is primarily a set of maps. It emphasizes land and geography and does so at a district level. Other critical dimensions of the industrial system, such as output, labor, organizational strategy, and freight flows are described in other documents and given less attention here. Additionally, the region and nation are basic levels of economic geography that get less emphasis in the atlas, in order to focus on the most descriptive data available at the site level. The result is intended to shine new light on this core feature of the city and the industrial system.