Gilaki is an Iranian language belonging to the Caspian subgroup of the Northwestern branch, spoken in south of Caspian Sea by Gilak people. Gilaki is closely related to Mazandarani. The two languages of Gilaki and Mazandarani have similar vocabularies. The Gilaki and Mazandarani languages share certain typological features with Caucasian languages, reflecting the history, ethnic identity, and close relatedness to the Caucasus region and Caucasian peoples of the Gilak people and Mazandarani people.