The word Downtown is a term that is used mainly in North America in English to refer to the city center or the central business area of a city ( usually in the geographical, commercial or community sense).
It was coined in New York City, where he has been used since about 1830, to refer to the original town at the southern end of Manhattan Island reference. As New York grew, the city could only grow to the north, so up the river ( "up"). This all became known as " uptown" ( Upper Manhattan ) and according to the South and "downtown" ( Lower Manhattan ) to the north. Since many maps are displayed polar aligned, can be used as analogy "up" as the north and "down" understood as the south.
In the 19th century, the term was taken over gradually by other U.S. and Canadian cities to designate the historic city center. By 1880, the term did not appear in dictionaries, but was clearly established in the early 1900s as a formal term for the North American city.
For New York, the terms Downtown and Uptown denote the direction in which one moves within Manhattan. Man walking or driving downtown, so in the south, or uptown, towards the north.