Polish (jezyk polski, polszczyzna) is the official language of Poland. Polish is the main representative of the Lechitic branch of the Western Slavic languages. It originated in the areas of present-day Poland from several local Western Slavic dialects, most notably those spoken in Greater Poland and Lesser Poland.
Polish was once a lingua franca in various regions of Central and Eastern Europe, mostly due to the political, cultural, scientific and military influence of the Polish-Lithuanian Commonwealth. Although not that popular any more due to the Russian language influence, it is still sometimes spoken or at least understood in western border areas of Ukraine, Belarus and Lithuania as a second language.