Chinese music is considered one of the oldest in the world and was organized into four periods - the Formative Period from 300BC-400AD, the International Period from 401-959AD, the National Period from the 10th-19th century, and the World Music Period from 1950 onward. During the Formative Period, music was used in folk festivals honoring ancestors using instruments like stone chimes and clay ocarinas. The International Period marked the climax of Chinese music's development but it was also influenced by Western and Northern cultures. The National Period emphasized vocal music and instrumental music to accompany vocals using instruments like the pipa and chin.