To the ears of the common man, not particularly versed in linguistics, the phrase "the Yugoslav language" is quite normal. But try to casually drop it when a linguist, you will immediately see a grimace on his face, which often occurs at the musician, catch a false note. This is understandable. In linguistics there is no such thing as "Yugoslavian language." And yet, how is it? Until the 90's was the Socialist Republic of Yugoslavia and became be, and the state language, too, was. And it is absolutely fair to call the Yugoslav, even though for reasons of elementary logic and norms of the Russian language as "Yugoslav" – meaning "pertaining to Yugoslavia / Yugoslavia." So what still is – "the Yugoslav language"? Until the political map of the world, there is a state like Yugoslavia was, respectively, and the state language, which was called Serbo-Croatian. Thus, "Yugoslavian language – the language of Serbo-Croatian. In fairness it should be noted that the "Yugoslav" one hundred percent of his can not be considered. Most of the country it said, but Slovenia and Macedonia – no.
But since another, absolutely Yugoslav, language was not, then we will assume the Yugoslav Serbo-Croatian language. In principle, the Serbs and Croats began to speak the same language since the VI century, ie from the time when their ancestors were on the Balkan Peninsula. In this case, the Serbs were convinced they speak Serbian, Croatian and saw it as their language Croatian. By and large, these languages differ from each other almost as much as the Moscow dialect to dialect Pomorie.