An electric guitar is a type of guitar that uses electronic pickups to convert the vibration of its steel-cored strings into electrical current. The signal may be electrically altered to achieve various tonal effects prior to being fed into an amplifier, which produces the final sound which can be either an electrical sound or an acoustic sound. Distortion pedals can change the sound that is emitted from the amplifier.

The electric guitar is used extensively in many popular styles of music, including almost all genres of rock and roll, country music, pop music, jazz, blues, rap and even contemporary classical music. Its distinctive sound and intimate association with many legendary internationally-famous musicians has made it the signature instrument of late twentieth-century music.

Specialised steel guitars, although they are also electric instruments descended from the guitar, are normally not considered electric guitars but rather as a separate instrument. This distinction has important consequences on claims of priority in the history of the electric guitar.

Types of electric guitar

There are two main types of electric guitar:

• Hollow body electric guitars, sometimes called semi-acoustic, and themselves of two types:
  • Archtop electric guitars with a full sound box.
  • Thin hollow body guitars.
• Solid body guitars.

Acoustic-electric guitars

Some acoustic guitars are fitted with pickups purely as an alternative to using a microphone. These are also sometimes called semi-acoustic, and sometimes acoustic electric, but are regarded as acoustic rather than electric guitars. The terminology is not generally agreed, and the line hard to draw.

Seven-string guitars

Seven-string guitars exist, most of which add a low B string below the E. They were popularized by Steve Vai and others in the 1980s, and have been recently revived by some nu metal bands(such as Korn). Jazz guitarists using a seven-string include veteran jazz guitarist Bucky Pizzarelli and his son John Pizzarelli. Another common seven-string arrangement is a second G string situated beside the standard G string and tuned an octave higher, in the same manner as a twelve-stringed guitar (see below).

Eight-string guitars

There are even eight-string electric guitars, such as the one played by Charlie Hunter (manufactured by Novax Guitars), but they are extremely unusual. The largest manufacturer of 8- to 14-strings is Warr Guitars. Their models are used by Trey Gunn (of King Crimson) who has his own signature line from the company.

Twelve string guitars

Twelve string electric guitars feature six pairs of strings, usually with each pair tuned to the same note, although in different octaves. The pairs of strings are played together as one, so the technique and tuning are the same as a conventional guitar, although creating a much fuller tone. They are used almost solely to play chords and are relatively common in folk rock music.

Double Neck guitars

Jimmy Page, an innovator of hard rock, used and made famous custom Gibson electric guitars with two necks - essentially two instruments in one; in his case, a 6-string and 12-string guitar, to replicate his use of two different guitars when playing live "Stairway to Heaven" so that he didn't have to pause to switch from one section to another. These are commonly known as double-neck (or, less commonly, "twin-neck") guitars. The purpose is to obtain different ranges of sound from each instrument; typical combinations are six-string and four-string (guitar and bass guitar) or, more commonly, a six-string and twelve-string. Such a combination may come handy when playing ballads live, where the 12-string gives a mellower sound as accompaniment, while the 6-string may be used for a guitar solo. English progressive rock bands such as Genesis took this trend to its zenith using custom made instruments produced by the Shergold company. Rick Nielsen, guitarist for Cheap Trick, uses a variety of custom guitars, many of which have five necks, with the strap attached to the body by a swivel so that the guitar can be rotated to put any neck into playing position - more for comic effect than for actual usefulness. Guitar virtuoso Steve Vai occasionally uses a triple-neck guitar; one neck is twelve string, one is six string and the third is a fretless six string.