Tar (Persian: تار) is an Iranian long-necked, waisted instrument, shared by many cultures and countries including Iran, Azerbaijan, Armenia, Georgia, and others near the Caucasus region. The older and more complete name of the tār is čāhārtār or čārtār, meaning in Persian “four string”, (čāhār frequently being shorted to čār). This is in accordance with a practice common in Persian-speaking areas of distinguishing lutes on the basis of the number of strings originally employed. Beside the čārtār, these include the dotār (دوتار, “two string”), setār (سهتار, “three string”), pančtār (پنجتار “five string”), and šaštār or šeštār (ششتار “six string”).
It was invented in the 18th century and has since become one of the most important musical instruments in Iran and the Caucasus, particularly in Persian classical music, and the favoured instrument for radifs.