ABSTRACT
The protolanguage is a formula that helps us understand the differences of the later varieties of a language. The reconstruction is a two-way street, going from existing languages to the protolanguage and back again. While Proto-Turkic is a reconstructed language, Ancient Turkic is a language that has existed and has been spoken by a language community. An Urheimat ‘original homeland’ denotes the region where a language has come into being, in our case, the place of the formation of Turkic. Sources available for the reconstruction of Proto-Turkic include comparison of present-day Turkic languages, historical documents written in Turkic languages, loans copied by non-Turkic languages from Turkic languages, and loans copied from non-Turkic languages by one or more Turkic languages. Languages are genealogically related if and only if their basic linguistic features can be considered the result of continuous and regular changes of the features of a common protolanguage.
