Several guzheng on display in a store
|Literal meaning||ancient zheng|
The zheng (Chinese: ?; Wade-Giles: cheng) or guzheng (Chinese: ; literally: "ancient zheng"), also known as a Chinese zither, is a Chinese plucked string instrument with a more than 2,500-year history. The modern guzheng commonly has 21 strings, is 64 inches (1.6 m) long, and is tuned in a major pentatonic scale. It has a large, resonant soundboard made from Paulownia. Other components are often made from other woods for structural or decorative reasons. Guzheng players often wear fingerpicks made from materials such as plastic, resin, tortoiseshell, or ivory on one or both hands.
The guzheng is ancestral to several other Asian zithers such as the Japanese koto, the Korean gayageum, Mongolian yatga, and the Vietnamese ?àn tranh. The guzheng should not be confused with the guqin, a Chinese zither with 7 strings played without moveable bridges.
The guzheng has gone through many changes during its long history. The oldest specimen yet discovered held 13 strings and was dated to around 500 BCE,  possibly during the Warring States period (475-221 BCE). The guzheng became prominent during the Qin dynasty (221-206 BCE). By the Tang Dynasty (618-907 CE) the guzheng may have been the most commonly played instrument in China.
There are varied accounts for how the guzheng came to be. An early guzheng-like instrument is said to have been invented by Meng Tian, a general of the Qin dynasty (221-206 BCE), largely influenced by the se. Some believe the guzheng was originally developed as a bamboo-tube zither as recorded in the Shuowen Jiezi, which was later redesigned and made from larger curved wooden boards and movable bridges. A third legend says the guzheng came about when two people fought over a 25-string se. They broke it in half, one person receiving a 12-string part and another the 13-string part.
Strings were once made of silk. During the Qing dynasty (1644-1912 CE) the strings transitioned to bare wire such as brass. Modern strings are almost always steel coated in nylon. First introduced in the 1970s these multi-material strings increased the instrument's volume while maintaining an acceptable timbre.
The guzheng is often decorated. Artists create unique cultural and artistic content on the instrument. Decorations include carved art, carved lacquer, straw, mother-of-pearl inlays, painting, poetry, calligraphy, shell carving (jade) and cloisonné.
Playing styles are first divided between Northern and Southern before being further subdivided into specific regional schools. Regional schools that are part of the Northern style include Henan, Shaanxi, Shandong, and Zhejiang. Regional schools included in the Southern style include Chaozhou, Hakka, and Fujian. 
Examples of Northern pieces include High Mountain and Running River and Autumn Moon over the Han Palace from the Shandong school. Southern style can be represented by Jackdaw Plays with Water () from the Chaozhou school and Lotus Emerging from Water ( ) from the Hakka school.
The guzheng is plucked by the fingers with or without plectra. Most modern players use plectra that are attached to up to four fingers on each hand. Ancient picks were made of mundane materials such as bamboo, bone, and animal teeth or by finer materials such as ivory, tortoiseshell, and jade. 
Traditional playing styles use the right hand to pluck notes and the left hand to add ornamentation such as pitch slides and vibrato by pressing the strings to the left of the movable bridges. Modern styles use both hands to play on the right side of the strings. There are many techniques used to strike notes. One iconic sound is a tremolo produced by the right thumb rotating rapidly around the same note.
New techniques include playing harmony and counterpoint with the left hand. Pieces in the new style include Harvest Celebration (atonal pieces have been composed since the 1980s., Zhao Yuzhai, 1955), Fighting the Typhoon ( , Wang Changyuan, 1965) and the guzheng concerto Fantasia of Miluo River (Li Huanzhi, 1984). Experimental,
A modern playing technique, influenced by Western music, uses the left hand to provide harmony and bass notes; this gives the guzheng a more flexible musical range, permitting harmonic progression. It has its limitations, preventing the subtle ornamentation provided by the left hand in traditional music. Guzheng students who take the Central Conservatory of Music examinations are required to learn traditional and modern pieces.
Notable 20th-century players and teachers include Wang Xunzhi (, 1899-1972), who popularized the Wulin zheng school based in Hangzhou, Zhejiang; Lou Shuhua, who rearranged a traditional guzheng piece and named it Yu Zhou Chang Wan; Liang Tsai-Ping (1911-2000), who edited the first guzheng manual (Nizheng Pu) in 1938; Cao Dongfu (1898-1970), from Henan; Gao Zicheng (born 1918) and Zhao Yuzhai (born 1924), both from Shandong; Su Wenxian (1907-1971); Guo Ying (born 1914) and Lin Maogen (born 1929), both from Chaozhou; the Hakka Luo Jiuxiang (1902-1978) and Cao Guifen and Cao Zheng (, 1920-1998), both of whom trained in the Henan school. The Cao family of Henan are known as masters of the guzheng.
Notable 21st-century Chinese guzheng players include Xiang Sihua, Wang Zhongshan, Yuan Sha, Chang Jing and Funa. Although most guzheng music is Chinese classical music, the American composer Lou Harrison (1917-2003) played and composed for the instrument. Contemporary guzheng works have also been written by the non-Chinese composers Halim El-Dabh, Kevin Austin, David Vayo, Simon Steen-Andersen, and Jon Foreman.
It was played by Zhang Yan (, 1945-1996), performing and recording with Asian American jazz bandleader Jon Jang. Other musicians playing in non-traditional styles include Wu Fei, Xu Fengxia, Randy Raine-Reusch, Mohamed Faizal, B. Mohamed Salim, Mei Han, Bei Bei He, Zi Lan Liao, Levi Chen, Andreas Vollenweider, Jaron Lanier, Mike Hovancsek, Chih-Lin Chou, Liu Le and David Sait. Koto player Brett Larner developed innovative works for the guzheng and played the instrument in a duet with electronic musician Samm Bennett on his CD, Itadakimasu.
In the television drama series My Fair Princess, actress Ruby Lin's character Xia Ziwei plays the guzheng (although she mimes to the music). It is featured in the 1980 pop hit, "Everybody's Got to Learn Sometime", by the Korgis.
In the film Kung Fu Hustle, the assassins known as The Harpists play a long zither to generate bladed and percussive attacks. The instrument has raised bridges like a guzheng but its body is shaped like a guqin. The sound is that of a guzheng. 
The guzheng has been used in rock music by Chinese performer Wang Yong of Cui Jian, the English musician Jakko Jakszyk on the 2011 Jakszyk, Fripp & Collins album A Scarcity of Miracles), J.B. Brubaker of August Burns Red on "Creative Captivity" from the 2013 album, Rescue & Restore, and the virtual band Gorillaz on "Hong Kong" (from the 2005 Help! A Day in the Life compilation). Jerusalem-based multi-instrumentalist Bradley Fish used the guzheng with a rock-influenced style and electronic effects on his 1996 collaboration, "The Aquarium Conspiracy" (with Sugarcubes/Björk drummer Sigtryggur Baldursson), and is the most widely recorded artist of loops for the instrument.
Throughout the centuries, the zheng became the parent instrument of the Asian zither family as it spread from China to a number of adjacent countries giving birth to the Japanese koto, the Korean kayagum and the Vietnamese dan tranh.
The kayagum, the most popular South Korean instrument, is a 12-string half-tube plucked zither (H/S 312.22.5) (Plate 7). It resembles the Chinese zheng, Mongolian yatga, Japanese koto, and Vietnamese dan tranh. All these instruments descend from a common model, the ancient zheng.
According to the Shuo Wen the cheng was a bamboo-tube zither. [...] The bamboo tube eventually was replaced by a larger curved wooden board and while in one or two zither types fixed or movable bridges were used, the noble ch'in remained an unfretted instrument. Despite the fact that the cheng is not mentioned in the Classics, it is mentioned here because of its old age. The movable bridges which allowed variable tunings linked the cheng securely with popular music. It still exists side by side with the distinguished ch'in and se. Since the fourth or third centuries B.C. there existed another form of the se, a zither with five (to thirteen) strings, called chu (M 1375). The instrument is not mentioned in the Classics.