This interdisciplinary course focuses on the structural development and contrastive analysis of Iranian languages including Dari, Farsi, Tajiki, Balochi, Kurdish, Pashto, and Zazaki. The lectures begin with an overview of ancient and medieval Iranian languages and then describe modern Iranian languages' historical and structural development. The course also examines the role of language in maintaining cultural identity and demonstrates the type and mechanism of the development of Iranian languages. The lecture materials are based on texts and articles written by theoretical linguists, sociolinguists, typologists, and descriptive and historical linguists.