Haegeum is

Haegeum

The haegeum is a traditional Korean two-stringed fiddle. It produces sound by rubbing a bow made of horsehair between two twisted silk strings, which are stretched over a small resonator crafted from bamboo root. The name Haegeum is recorded to have originated from the Hae tribe, who lived near the border region between present-day Mongolia and China and were known for playing a similar bowed instrument. The haegeum was introduced to Korea from the Song dynasty during the Goryeo dynasty(1114 ) period and was subsequently adapted and refined to suit Korean musical aesthetics. 

In playing the instrument, the right hand makes a friction between the bow and the string while the left hand covers and grabs the two strings at once or release from them to tune in the height of a note. The sound is made only by the performer's musical sense without any other supplementary device. The jewel of playing Haegeum is to make charming sounds by using 'Yeokanbeop' a technique whereby the two strings are grabbed and pressed together, or release and shaken. This is different from 'Eolhu' of China, a similar instrument with Haegeum as a rubbed string with which musical notes are plucked with fingertips under the technique called 'Gyeonganbeop.'

Haegeum is the only musical instrument fully equipped with traditional eight materials - 金 (gold), 石 (stone), 絲 (silk), 竹 (bamboo), 匏 (gourd), 土 (soil), 革 (leather), and 木 (wood).