Polish (język polski, polszczyzna) is the official language of Poland. It is the most spoken West Slavic language.
Today Polish is the official language of Poland; it is spoken by most of the 38 million inhabitants of Poland (census 2002). There are also native speakers of Polish in western Belarus and Ukraine, as well as in eastern Lithuania (in the area of Vilnius), southeastern Latvia (around Daugavpils), northern Romania, and northeastern part of Czech Republic. Because of emigration from Poland in various periods, millions of Polish-speakers may be found in countries such as Germany, France, Ireland, Australia, Mexico, Israel, Brazil, Iceland, the United Kingdom, United States, etc. The estimated number of Poles who live beyond the borders of Poland is 10 million. It is not clear, however, how many of them can actually speak Polish - the estimates range from 3.5 to 10 million. This puts the number of native speakers of Polish worldwide at between 40 and 48 million. According to Ethnologue, there are about 43 million first language speakers of Polish worldwide.
Source - Wikipeadia.com