Kajkavian
The major cities in northern Croatia are located in what was historically a Kajkavian-speaking area, mainly Zagreb, Koprivnica, Krapina, Križevci, Varaždin, Čakovec. The typical archaic Kajkavian is today spoken mainly in Hrvatsko Zagorje hills and Međimurje plain, and in adjacent areas of northwestern Croatia where immigrants and the Štokavian standard had much less influence. The most peculiar Kajkavian dialect "(Baegnunski)" is spoken in Bednja in northernmost Croatia. Many of northern Croatian urban areas today are partly Štokavianized due to the influence of the standard language and immigration of Štokavian speakers.
List of lingua francas
Serbo-Croatian is a lingua franca in several of the territories of the former Yugoslavia, that is, modern Bosnia and Herzegovina, Croatia, Montenegro and Serbia. In those four countries it is the main native language, and is also spoken by ethnic minorities. For example, a Hungarian from Vojvodina and an Italian from Istria might use it as a shared second language. Most people in Slovenia and Macedonia can understand or speak Serbo-Croatian as well. It is a pluricentric language and is commonly referred to as Bosnian, Croatian, Serbian or Montenegrin depending on the background of the speaker.