Koreatown offers a number of great traditional restaurants, grocery stores and various bars and clubs. So if you seek e.g. Korean food, Korean bookstores or Korean stationery, this is the place where you should go. This part of NYC is still growing and the Korean culture attracts more and more people every year.
Wikipedia https://en.wikipedia.org/wiki/Koreatown,_Manhattan
Info https://www.timeout.com/newyork/manhattan/koreatown-nyc-neighborhood-guide
Coordinates 40°44'51.511" N -73°59'11.457" E