There is mainly one rule: If you're white, it's best to stay in NW. If the cost of living is too high for you in some of the nicer areas of NW, there's always Shaw and Petworth. Both of those neighborhoods are run down and slightly dangerous, but they get you close to things. DOn't go to Anacostia at night, and especially don't walk around there alone.
www.wmata.com has a map of DC with all of the metro stations. Those are named after the neighborhoods that they are in.
no
Washington, DC is one complete city. Like all cities it has sections and neighborhoods, many of which have names, but it is a single city.
Washington, DC
Washington DC
Washington - Baltimore Washington International, DC, USA (BWI) Washington - Washington - All Airports, DC, USA (WAS) Washington - Ronald Reagan National Airport, DC, USA (DCA) Washington - Washington Dulles, DC, USA (IAD)
there are no counties in Washington DC because Washington DC is a city itself.
Washington, DC
Washington DC
Yes, NASA's headquarters is located in Washington DC.
On the mall in Washington, DC.
Washington DC was named by george washington.