The article prouves that Makhmud Kashgari, eminent scholar of XI century, describing languages of Turkik tribes reveals their common and specific points, and tries to classify them. It is underlined that Oghuz and Kipchak dialects being from the same linguistic group are mutually raleted at different levels. Makhmud Kashgari also undertakes an attempt to analyze the important information on the forming of literary linguistic networks. The present article emphasizes the fact hat the first literary language appeared from ont of the branches of the od Uzbek