Chakavian
Chakavian or Čakavian , , ( , proper name: "čakavica" or "čakavština" , own name: "čokovski, čakavski, čekavski") is a dialect of the Serbo-Croatian language spoken by a minority of Croats. It has a low mutual intelligibility with Shtokavian. There is much internal diversity, to the point where intelligibility between the northern and southern varieties of Chakavian is low. All three main Serbo-Croatian dialects are named after their most common word for "what?", which in Čakavian is "ča" or "ca". Chakavian is spoken mainly in the northeastern Adriatic: in Istria, Kvarner Gulf, in most Adriatic islands, and in the interior valley of Gacka, more sporadically in the Dalmatian littoral and central Croatia.
Shtokavian
Croatian has had a long tradition of Shtokavian vernacular literacy and literature. It took almost four and half centuries for Shtokavian to prevail as the dialectal basis for the Croatian standard. In other periods, Chakavian and Kajkavian dialects, as well as hybrid Chakavian–Kajkavian–Shtokavian interdialects "contended" for the Croatian national koine – but eventually lost, mainly due to historical and political reasons. By the 1650s it was fairly obvious that Shtokavian would become the dialectal basis for the Croatian standard, but this process was finally completed in the 1850s, when Neo-Shtokavian Ijekavian, based mainly on Ragusan (Dubrovnik), Dalmatian, Bosnian, and Slavonian literary heritage became the national standard language.