The bouzouki (Greek: μπουζούκι; pronounced [buˈzuki]; plural: μπουζούκια) is a Greek musical instrument that was brought toGreece in the 1900s by immigrants from Asia Minor, and quickly became the central instrument to the rebetika genre and its music branches.  A mainstay of modern Greek music, the front of the body is flat and is usually heavily inlaid with mother-of-pearl. The instrument is played with a plectrum and has a sharp metallic sound, reminiscent of a mandolin but pitched lower. There are two main types of bouzouki. The trichordo (three-course) has three pairs of strings (known as courses), and the tetrachordo (four-course) has four pairs of strings.
The name "bouzouki" comes from the Turkish word "bozuk," meaning "broken" or "modified," and comes from a particular re-entrant tuning called "bozuk düzen," which was commonly used on its Turkish counterpart, the "saz-bozuk." It is in the same instrumental family as the mandolin and the lute. Originally the body was carved from a solid block of wood, similar to the saz, but upon its arrival in Greece in the early 1910s it was modified by the addition of a staved back borrowed from the Neapolitan mandola, and the top angled in the manner of a Neapolitan mandolins so as to increase the strength of the body to withstand thicker steel strings. The type of the instrument used in Rembetika music was a three-stringed instrument, but in the 1950s a four-string variety was introduced.
The Greek bouzouki is a plucked musical instrument of the lute family, called the thabouras or tambouras family. The tambouras has existed in ancient Greece, and can be found in various sizes, shapes, depths of body, lengths of neck and number of strings. The bouzouki and the baglamas are the direct descendants. The Greek marble relief, known as the Mantineia Base (now exhibited at the National Archaeological Museum of Athens), dating from 330-320 BC, shows a muse playing a variant of the pandoura.
From Byzantine times it was called pandouras and then tambouras. On display in the National Historical Museum of Greece is the tambouras of a hero of the Greek revolution of 1821, General Makriyiannis.
Other sizes have appeared and include the Greek instrument tzouras, an instrument smaller in size than standard bouzouki.
Following the 1919–1922 war in Asia Minor and the subsequent exchange of populations between Greece and Turkey, the ethnic Greeks fled to Greece. The early bouzoukia were mostly three-string (trichordo), with three courses (six strings in three pairs) and were tuned in different ways, as to the scale one wanted to play. At the end of the 1950s, four-course (tetrachordo) bouzoukia started to gain popularity. The four-course bouzouki was made popular by Manolis Chiotis who also used a tuning akin to standard guitar tuning, which made it easier for guitarists to play bouzouki, even as it angered purists. The first recording was made in 1958.
The Irish bouzouki, with four courses, a flatter back, and differently tuned from the Greek bouzouki, is a more recent development, stemming from the introduction of the Greek instrument into Irish music by Johnny Moynihan around 1965, and its subsequent adoption by Andy Irvine, Alec Finn, Dónal Lunny, and many others.
The three-course bouzouki (trichordo)
This is the classical type of bouzouki that was the mainstay of most Rebetiko music. It has fixed frets and it has 6 strings in three pairs. In the lower-pitched (bass) course, the pair consists of a thick wound string and a thin string tuned an octave apart. The conventional modern tuning of the trichordo bouzouki is Dd-aa-dd. This tuning was called the "European tuning" by Markos Vamvakaris, who described several other tunings, ordouzenia, in his autobiography. The illustrated bouzouki was made by Karolos Tsakirianof Athens, and is a replica of a trichordo bouzouki made by his grandfather for Markos Vamvakaris and became more famous from Manolis Chiotis. The absence of the heavy mother of pearl ornamentation often seen on modern bouzoukia is typical of bouzoukia of the period. It has tuners for eight strings, but has only six strings, the neck being too narrow for eight. The luthiers of the time often used sets of four tuners on trichordo instruments, as these were more easily available, since they were used on mandolins.
The four-course bouzouki (tetrachordo)
This type of bouzouki has 8 metal strings which are arranged in 4 pairs, known as courses, typically tuned Cc Ff aa dd (i.e., one whole step below the four high strings of a guitar). In the two higher-pitched (treble) courses, the two strings of the pair are tuned to the same note. In the two lower-pitched (bass) courses, the pair consists of a thick wound string and a thin string tuned an octave apart. These 'octave strings' add to the fullness of the sound and are used in chords and bass drones (continuous low notes that are played throughout the music). The guitar-like tuning was introduced by composer and soloist Manolis Chiotis, who found it better suited to the kind of virtuoso playing he was famous for. Traditionalists shun the 4-course as they feel it alters the character of the instrument. Many musicians such as the aforementioned Chiotis and Giorgos Zampetas began using specially designed pickups to achieve a slightly thicker humbucker-like sound in the mid-1960s. These pickups are widely used by several Greek artists today and came in active and (usually) passive versions.
The Greek baglamas
The Greek baglamas (Greek μπαγλαμάς) or baglamadaki (Greek μπαγλαμαδάκι), is very different from the Turkish bağlama. The treble bouzouki is pitched an octave higher (nominally D-A-D), with unison pairs on the four highest strings and an octave pair on the lower D. Musically, the baglamas is most often found supporting the bouzouki in thePiraeus style of rembetika.