Võro is a language belonging to the Finnic branch of the Uralic languages. It is spoken in the South-Eastern part of Estonia, where also Seto is spoken.
Võro has preserved the system of vowel harmony that was present in Proto-Finnic. The vowel harmony system distinguishes front, back and neutral vowels, much like the system found in Finnish. A word cannot contain both front and back vowels.
From its closest Finnic language neigbours, Estonian doesn’t have vowel harmony but Finnish has.