(or preceding) line. A rhyme scheme is the pattern of rhyming lines in a poem. History In many languages, including modern European languages and Arabic, poets use rhyme in set patterns as a structural element for specific poetic forms, such as ballads, sonnets and rhyming couplets. Some rhyming schemes have become associated with a specific language, culture or period, while other rhyming schemes have achieved use across languages, cultures or time periods. However, the use of structural rhyme is not universal even within the European tradition. Much modern poetry avoids traditional rhyme schemes. The earliest surviving evidence of rhyming is the Chinese Shi Jing (ca. 10th century BCE). Rhyme is also occasionally used in the Bible. Classical Greek and Latin poetry did not usually rhyme, but rhyme was used very occasionally. For instance, Catullus includes partial rhymes in the poem Cui dono lepidum novum libellum. The ancient Greeks knew rhyme, and rhymes in The Wasps by Aristophanes are noted by a translator. Rhyme became a permanent - even obligatory - feature of poetry in Hebrew language, around the 4th century CE. It is found in the Jewish liturgical poetry written in the Byzantine empire era. This was realized by scholars only recently, thanks to the thousands of piyyuts that have been discovered in the Cairo Geniza. It is assumed that the principle of rhyme was transferred from Hebrew liturgical poetry to the poetry of the Syriac Christianity (written in Aramaic), and through this mediation introduced into Latin poetry and then into all other languages of Europe. Rhyme is central to classical Arabic poetry tracing back to its 6th century pre-Islamic roots. According to some archaic sources, Irish literature introduced the rhyme to Early Medieval Europe, but that is a disputed claim. In the 7th century, the Irish had brought the art of rhyming verses to a high pitch of perfection. The leonine verse is notable for introducing rhyme into High Medieval literature in the 12th century. Rhyme entered European poetry in the High Middle Ages, in part under the influence of the Arabic language in Al Andalus (modern Spain). Arabic language poets used rhyme extensively from the first development of literary Arabic in the sixth century, as in their long, rhyming qasidas. Since dialects vary and languages change over time, lines that rhyme in a given register or era may not rhyme in another, and it may not be clear