Nassau is the capital of the Bahamas. It has a population of around 250,000.
Naypyidaw is the capital of Burma(Myanmar). It was founded in 2005, and has a population of around 1 million.
Someone is poor if they do not have much money. An area might be described as poor if it is run down and a lot of poor people live there.
You also use poor to describe something you feel sorry for. For example, if you see a hurt bird you might say "oh, look at the poor bird".