1. History of the Guitar The Electric Guitar
Why electricity and guitar had to meet. Already in the 1800's people began experimenting with electrically powered instruments. (e.g. music boxes and player pianos) Amplified instruments however do not appear before the 1920's when electrical amplification was invented by the radio industry. By the 1930's the need for an amplified guitar became apparent. This period is referred to as 'the big band era'. The acoustic guitar was no match for the brass sections in the jazz orchestras. This shortcoming was the major basis for the electric guitar to evolve. They simply needed a guitar with a volume knob.
The first steps. You can imagine the first electric guitars didn't really resemble the ones we're familiar with. In fact they were more like acoustic guitars with rudimentary magnetic pickups attached to them. With these pickups the vibrations of the strings were converted into electrical signals. Those impulses were then amplified through a set of speakers. This was already happening in the early 1920's and the theory still applies to our modern electric guitars.
The Frying Pans. The first electric guitar for the general public was build in They were called "Frying Pans". The picture below shows clearly why.
This Hawaiian guitar was mostly
made out of aluminum and was the
first commercially successful
electric guitar. The very first Frying Pan, also
known as the Mona Lisa of musical
instruments, still exists and is
considered to be priceless. Despite the success a major
problem occurred with the electric
guitars made so far. They all had a
hollow body and vibrated a lot
which was of course disastrous for
the sound it produced and for the
guitar itself. This effect is known as the feedback.
From hollow to solid body. The electrical guitar was a great success from day one. But the problem with the feedback caused guitar bodies to crack. A solution was necessary but also evident in the way it appeared. When a hollow body causes problems you simply build a solid body. It's early 1940's.
Mass producing 'Fenders and casters'. The first mass produced electric guitar was build in 1950 in Leo Fender's workshop. It was first called the Broadcaster but quickly renamed to the Telecaster due to patent related issues Years later, in 1954, Fender's next guitar, called the Stratocaster, was presented to the public. By now the electric guitar was so successful that other companies started to manufacture their own guitar brands. The Gibson Les Paul guitar has been made in those days. Famous means expensive! Through the 1960's and the 1970's Fender and Gibson were not only the leading electric guitar brands, they were also very expensive. They stood for quality and durability but were to high-priced for the 'common people'. Cheaper imitations filled up the market but it was known they produced an inferior sound and were less playable. In the 1980's out of Japan came guitars of similar quality as the famous American models. As a result Fender and Gibson were forced to make less expensive guitars.
From history to future. Even today Fender and Gibson represent the standard for quality electric guitars. But they're no longer alone out there. And as technologies and materials evolve so does the guitar. With computer chips and matching software possibilities are endless. Electric guitars have become true synthesizers with strings
History of the Guitar
A Brief History of the Guitar       
by Paul Guy
                    
The guitar is an ancient and noble instrument, whose history can be traced back over 4000 years. Many theories have been advanced about the instrument's ancestry. It has often been claimed that the guitar is a development of the lute, or even of the ancient Greek kithara. Research done by Dr. Michael Kasha in the 1960's showed these claims to be without merit. He showed that the lute is a result of a separate line of development, sharing common ancestors with the guitar, but having had no influence on its evolution. The influence in the opposite direction is undeniable, however - the guitar's immediate forefathers were a major influence on the development of the fretted lute from the fretless oud which the Moors brought with them to to Spain.
"Queen Shub-Ad's harp" (from the Royal Cemetery in Ur)
A tanbur is defined as "a long-necked stringed instrument with a small egg- or pear-shaped body, with an arched or round back, usually with a soundboard of wood or hide, and a long, straight neck". The tanbur probably developed from the bowl harp as the neck was straightened out to allow the string/s to be pressed down to create more notes. Tomb paintings and stone carvings in Egypt testify to the fact that harps and tanburs (together with flutes and percussion instruments) were being played in ensemble years ago.
In this 1972 photo, Adolph Rickenbacker holds the original prototype of the "frying pan" electric guitar.
Electric guitar pioneer Charlie Christian helped re-define the role of the guitar player in the swing band ensemble.
Although Lloyd Loar experimented with an electrostatic pickup designed to amplify the sound produced by an acoustic guitar in 1923, credit for the first significant electromagnetic guitar pickup is usually given to George Beauchamp who created and patented the 1931 "Frying Pan" lap-steel instrument (the wood prototype - the production models were made of cast aluminum).
The wood neck and body of the "Frying Pan" are the work of Harry Watson, who had been the superintendant of the National Company. To take the idea to market, Beauchamp enlisted the aid of Alfred Rickenbacker (Alfred was the cousin of famous flying ace, Eddie Rickenbacker) with whom he formed the Electro String Company. Rickenbacker instruments were born.

2. A modern acoustic guitar.
The earliest stringed instruments known to archaeologists are bowl harps and tanburs. Since prehistory people have made bowl harps using tortoise shells and calabashes as resonators, with a bent stick for a neck and one or more gut or silk strings. The world's museums contain many such "harps" from the ancient Sumerian, Babylonian, and Egyptian civilizations. Around CE more advanced harps, such as the opulently carved 11-stringed instrument with gold decoration found in Queen Shub-Ad's tomb, started to appear.
From four-, to five-, to six-string guitar
As we have seen, the guitar's ancestors came to Europe from Egypt and Mesopotamia. These early instruments had, most often, four strings - as we have seen above, the word "guitar" is derived from the Old Persian "chartar", which, in direct translation, means "four strings". Many such instruments, and variations with from three to five strings, can be seen in mediaeval illustrated manuscripts, and carved in stone in churches and cathedrals, from Roman times through till the Middle Ages. Right: Roman "guitar", c:a 200 CE.
Two electric 12 strings, a Shergold Modulator 12 (top) and a Maton TB36/12 (bottom); the latter is a copy of the Rickenbacker 360/12
The oldest preserved guitar-like instrument
                              At 3500 years old, this is the ultimate vintage guitar! It belonged to the Egyptian singer Har-Mose. He was buried with his tanbur close to the tomb of his employer, Sen- Mut, architect to Queen Hatshepsut, who was crowned in 1503 BCE. Sen-Mut (who, it is suspected, was far more than just chief minister and architect to the queen) built Hatshepsuts beautiful mortuary temple, which stands on the banks of the Nile to this day.
                                                                                          
Har-Moses instrument had three strings and a plectrum suspended from the neck by a cord. The soundbox was made of beautifully polished cedarwood and had a rawhide "soundboard". It can be seen today at the Archaeological Museum in Cairo.
The modern "classical" guitar took its present form when the Spanish maker Antonio Torres increased the size of the body, altered its proportions, and introduced the revolutionary "fan" top bracing pattern, in around His design radically improved the volume, tone and projection of the instrument, and very soon became the accepted construction standard. It has remained essentially unchanged, and unchallenged, to this day.
Guitar by Antonio Torres Jurado, 1859
An acoustic guitar is a guitar that uses only acoustic methods to project the sound produced by its strings. The term is a retronym, coined after the advent of electric guitars, which on electronic amplification to make their sound audible.
A modern acoustic guitar.
In this image, all the different parts of the guitar are indicated. Some can only be found on electric guitars, some only on acoustic guitars. I will now give a brief description of every part indicated, from top to bottom.
Guitar picks have been around for centuries. Early picks were cut from bone, wood, shell, metal, amber, or a host of other materials by guitarists. Those picks were made for each guitar players’ personal needs and styles. Modern mass produced picks were introduced in 1922.
The lap steel guitar is a type of steel guitar, from which other types developed.
There are three main types of lap steel guitar:
Lap slide guitars, the first developed, which use a similar sound box to a Spanish guitar. These were originally called Hawaiian guitars and included versions that had a factory raised nut, but also included Spanish guitars with a nut extender.
Resonator guitars, particularly those with square necks, but would include round neck versions with a raised nut.
Electric lap steel guitars, which include the first commercially successful solid body instruments. These were originally marketed as Electric Hawaiian guitars. There are two types: one that sits on the musician's lap and a second version that has legs and was called a console version, but did not include pedals or knee levers. Electric lap steels are typically made with six to ten strings
This site has an abundance of additional information on guitars.