This census data indicates that many of the "other" races are located in the Western part of the US. The blue runs along the US/Mexico border so the "other" race in this category is most likely people crossing the border. Maps like these are very useful in understanding census data because it lets the person visualize it instead of look at numbers and percentages.
This map shows the regions in which the black population is highest. This is mostly in the Southeast of the US with many in Georgia, Mississippi and Louisiana.
The asian map is different than the other two. Here it is seen that there is not one area of the US that is totally dominated by asians. The largest population looks to be in California, but it is rather spread out among the entire US.
