The Classic of Poetry is the oldest existing collection of Chinese poetry, comprising 305 works dating from the 11th to 7th centuries BC. It is one of the "Five Classics" traditionally said to have been compiled by Confucius, and has been studied and memorized by scholars in China and neighboring countries over two millennia. Since the Qing dynasty, its rhyme patterns have also been analysed in the study of Old Chinese phonology. The content of the Poetry can be divided into two main sections: the "Airs of the States," and the eulogies and hymns. The "Airs of the States" are shorter lyrics in simple language that are generally ancient folk songs; while the "Eulogies" section tend to be longer ritual or sacrificial songs, usually in the forms of courtly panegyrics and dynastic hymns.