Poland is a country located in Central Europe, bordered by Germany to the west, the Czech Republic and Slovakia to the south, Ukraine and Belarus to the east, and the Baltic Sea and Kaliningrad Oblast to the north. It has an area of 312,679 square kilometers and a population of approximately 38.5 million people. The capital and largest city is Warsaw. The official language is Polish, and the currency is the Polish złoty. Poland has a long and complex history, with its first known state dating back to the 10th century. It has been a part of many different empires and has experienced significant political and social changes throughout its history. Today, Poland is a parliamentary republic and a member of the European Union, NATO, and the United Nations.