The guitar is a musical instrument with ancient roots that is used in a wide variety of musical styles. It typically has six strings, but four, seven, eight, ten, and twelve string guitars also exist.

Guitars are recognized as one of the primary instruments in blues, country, flamenco, rock music, and many forms of pop. There is also a solo classical instrument. Guitars may be played acoustically, where the tone is produced by vibration of the strings and modulated by the hollow body, or they may rely on an amplifier that can electronically manipulate tone. Such electric guitars were introduced in the 20th century and continue to have a profound influence on popular culture.

Traditionally guitars have usually been constructed of combinations of various woods and strung with animal gut, or more recently, with either nylon or steel strings. Guitars are made and repaired by luthiers.

An acoustic guitar is one not dependent on an external device to be heard but uses a soundboard which is a wooden piece mounted on the front of the guitar's body. The acoustic guitar is quieter than other instruments commonly found in bands and orchestras so when playing within such groups it is often externally amplified. Many acoustic guitars available today feature a variety of pickups which enable the player to amplify and modify the raw guitar sound.

Electric guitars can have solid, semi-hollow, or hollow bodies, and produce little sound without amplification. Electromagnetic pickups convert the vibration of the steel strings into electrical signals which are fed to an amplifier through a cable or radio transmitter. The sound is frequently modified by other electronic devices or the natural distortion of valves (vacuum tubes) in the amplifier.

Modern guitar strings are manufactured in either metal or organo-carbon material. Instruments utilising "steel" strings may have strings made of alloys incorporating steel, nickel or phosphor bronze. Classical and flamenco instruments have historically used gut strings but these have been superseded by nylon and carbon-fibre materials. Bass strings for both instruments are wound rather than monofilament.

This article uses material from the Wikipedia article Guitar.