Thanks to Geoffrey for getting into the Community Area map vs. all the unofficial neighborhood maps of Chicago. I've said about the same thing to many others. I'd like to clarify that the Community Area map is official, but it's on the Federal level; if anyone wants to collect data/statistics for sub-areas of the city and compare changes over many decades, they'll use the Community Areas because these boundaries stay the same over time, one reason they were established. The various neighborhood maps are valuable to show this aspect of the cultural landscape as people perceive it. But I did learn that at least one of these was not created using scientifically defensible methods of finding out what people called various locations in terms of neighborhood name. We should also note that Chicago divides the map into regions and districts for specific purposes; these boundaries are different from each other and from the neighborhoods and the Community Areas. It's fun if you're a map nut like me, but it confuses some journalists.