Uzbek is a Turkic language that is the first official and only declared national language of Uzbekistan. The language of Uzbeks is spoken by some 27 million native speakers in Uzbekistan, 3–4 million in Afghanistan and around 5 million in Central Asia, making it the second-most widely spoken Turkic language after Turkish.
Uzbek belongs to the Eastern Turkic or Karluk branch of the Turkic language family. External influences include Arabic, Persian and Russian. One of the most noticeable distinctions of Uzbek from other Turkic languages is the rounding of the vowel /ɑ/ to /ɔ/, a feature that was influenced by Persian. Unlike other Turkic languages, vowel harmony is completely lost in Standard Uzbek, though it is (albeit somewhat less strictly) still observed in its dialects, as with its sister Karluk language Uyghur.
Source : Wkipedia