is a stringed musical instrument
played with the fingers
or a plectrum
Instruments like the guitar have been popular for at least 5,000 years; murals in Egypt show women playing instruments like the guitar from the time of the Pharaohs, but the name "guitar" appears
first in Spain in the 13th century.
It was probably a deriviation of the Arabic word qitara, the
name of an instrument that was brought into Spain by the Moors after the 10th Century.
The Spanish vihuela appears to be an intermediate form, with lute-style tuning and a small guitar-style body, but it is not clear
whether this represents a transitional form or simply a design that combined features from the two families of instruments.
Guitars have frets on the fingerboard, to fix the positions of the notes, or scale which gives them equal temperament.
Guitars usually have six strings, although there are variations on this, the most common being a twelve-string guitar, the seven string guitar, the ukulele, which has four
strings, and the bass guitar, which usually has four strings but also exists
in five, six and twelve-string versions. The vihuela was a guitar variation with six
double strings made of gut, which emerged in 16th century Spain.
A variety of different tunings are used. The most common by far, known as "standard tuning", is (low to high) E-A-d-g-b-e'.
Standard tuning has evolved to provide a good compromise of both simple fingering for many chords, and the ability to play common scales with minimal left hand movement.
Additionally, the separation of all adjacent string pairs, except one (g-b), by the same interval: a perfect
fourth (equivalent to 5 frets' distance), yields a symmetry and intelligibility to fingering patterns in this tuning. The major
third (four frets' distance) between the g and b strings, though undermining this clarity, facilitates the playing of many chords
and scales as mentioned above, and, more generally, provides some diversity in fingering possibilities: many figures which are
difficult to play on strings tuned a fourth apart are easy to play on strings tuned a third apart and vice versa.
Some common alternate tunings
which provides the same intervals as for a renaissance lute and so you can play with your guitar directly from tablature.
- D-G-d-g-b-d commonly used for blues or slide guitar
- D-A-d-g-b-e' frequently used in folk music, and by metal and Alt-rock bands
devised by Robert Fripp of King Crimson, used by most Guitar Craft students around the world. The tuning is in fifths like that of a cello or a violin and has a remarkably wide range.
- D-A-d-g-a-d' frequently used in Celtic music, and by artists such as Pierre Bensusan.
There are also tenor guitars,
baritone guitars tuned ADGCEA (or GDGCDG, GDGCEA, GCGCEG, ...) a fifth lower than a normal guitar, treble guitars tuned a fourth
higher than a standard (prime) guitar, and contrabass guitars, which are tuned one octave lower than prime guitars.
Broadly speaking, guitars can be divided into 2 categories:
- Acoustic guitars: The traditional guitar is not
dependent on any external device for amplification, unlike the electric guitar (see below). However, the unamplified guitar is
not a loud instrument, that is, it cannot "compete" with other instruments commonly found in bands and orchestras, in terms of
sheer audible volume. Many acoustic guitars are available today with built-in electronics to enable amplification. There are
several subcategories within the acoustic guitar group: classical and flamenco guitars, both of which use nylon and composite
strings, and steel string guitars, which includes the flat top, or "folk" guitar, the closely related twelve string guitar, and
the arch top guitar. A recent arrival in the acoustic guitar group is the acoustic bass guitar, similar in tuning to the electric
- Renaissance and Baroque guitars: These are the gracile ancestors of the modern classical guitar. They are substantially smaller and more delicate than the classical guitar, and generate
a much quiter sound. The strings are paired in courses as in a modern 12 string guitar, but they only have four or five courses of strings rather than six. They were more often
used as rhythm instruments in ensembles than as solo instruments, and can often be seen in that role in early music performances. (Gaspar Sanz' Instrucción de Música sobre la Guitarra Española of 1674 constitutes
the majority of the surviving solo corpus for the era.) Renaissance and Baroque guitars are easily distinguished because the
Renaissance guitar is very plain and the Baroque guitar is very ornate, with inlays all over the neck and body, and a
paper-cutout inverted "wedding cake" inside the hole.
- Classical guitars: These are typically strung with
nylon or gut, and amplification is provided by the resonant hollow body, and the vibration of the thin, pliant top. In all
acoustic guitars, the strings, though vibrating with sufficient energy to produce a strong sound, can not do so by themselves
because they are too small and thin: air merely slips around them rather than being projected outward. The joining of the strings
to a large membrane, the top, which they pull back and forth where they connect to it at the bridge, creates an effective
air-moving system because the top is large enough that the air can not readily side step its motion. Sound only travels at 330
meters per second -- somewhat quickly, perhaps -- but if we recall that a guitar string typically switches from backward motion
to forward motion every 1/600th of a second, we see that the air only has a chance to go about 1/2 meter , and the approximately
1/2 meter dimensions of a guitar top are enough to thwart its attempted evasive rush.
These guitars are normally played in a seated position and used to play classical music. Flamenco guitars are almost equal in construction, have a sharper sound, and are
used in flamenco. In Mexico, the popular mariachi band includes a range of guitars, from the tiny requinto to the guitarron, a guitar larger than a cello,
which is tuned in the bass register.The father of the modern classical guitar was Antonio Torres Jurado.
- Flat top
guitars: Similar to the Classical guitar, but with a
narrower, reinforced neck and stronger structural design, to sustain the extra tension of steel strings which produce a louder
and brighter tone, the acoustic guitar is a staple in folk, Old-time music, traditional and blues music.
- Resonator, resophonic or dobro guitars: Similar to the
flat top guitar, but with a metal resonator mounted in the middle of the top rather than an open sound hole. The purpose of the
resonator is to amplify the sound of the guitar; this purpose has been largely superseded by electrical amplification, but the
resonator is still played by those desiring its distinctive sound. This type of guitar is more commonly played face up, on the
lap of the seated player, and often with a metal or glass slide.
- 12 string guitars usually have steel strings and are
widely used in folk music and rock and roll. Rather than having only six strings, the 12-string guitar has pairs, like a mandolin. Each pair of strings is tuned either in unison (the two highest) or an octave
apart (the others). They are made both in acoustic and electric forms.
- Archtop guitars
are steel string, acoustic instruments which feature a violin-inspired design in which the top and back of the instrument are
carved in a curved rather than a flat shape. Lloyd Loar of the Gibson company invented
this variation of guitar after designing a style of mandolin of the same type. They
were immediately adopted by both jazz and country musicians, but fell out of style when rock and
roll grew popular since their design is not capable of extreme amplification.
- Acoustic bass guitars also have steel strings,
and match the tuning of the electric bass, which is likewise similar to the traditional double bass viol, the "big bass", a
staple of string orchestras and bluegrass bands alike.
- Electric guitars: Electric guitars can have solid,
semi-hollow or hollow bodies, and produce little or very low sound without amplification. Electromagnetic pickups convert the vibration of the steel
strings into electric signals which are fed to an amplifier through a cable or radio device. The sound is frequently modified by
other electronic devices or natural distortion of valves in the amplifier. The electric guitar is used extensively in blues and rock and roll, and was
commercialized by Gibson together with Les
Paul and independently by Leo Fender. The electric bass is similar in
tuning to the traditional double bass viol.
Hybrids of acoustic and electric guitars are also common. There are also more exotic varieties, such as double-necked guitars,
all manner of alternate string arrangements, fretless fingerboards (almost always reserved for bass guitars, meant to emulate the
sound of a stand-up bass), and such.