The greatest sound in the world was, and will always be, a goal for humankind to reach with an instrument. With the appearance of brass instruments, a simple guitar was not loud enough to be heard from the audience. So, in 1931, a great Jazzman known as Les Paul, created an evolution of the classic guitar, the electric guitar. It started with a simple tungsten pick-up to catch the vibration of the strings and evolved to today where there are multineck guitars with 12 strings each. But we can check all the parts of a guitar as it is made of a body mounted with a neck accompanied of a bridge and pick-ups and finally with some strings.
At first, you have the body. In the early years of the guitar, the body was called “hollow body” because of its sound chamber. This was made to amplify the vibration of the strings. If you add a pick-up, you can catch the magnetic field and add the sound through an amplifier. Then came the solid body. This one is a full piece a wood with no sound chamber in it but just the pick-ups attached to the body .Also, you have the bridge that is made to retain the strings in the body. You have different kind of brigde but most of them are floating brigde that is retained by coil spring directly attached at the body. On the bridge you can find a hole to put the “wammy bar”. You can use the wammy bar to tighten or loose the strings to change the sound you want to make.
Then there is the neck. Usually made of rosewood, maplewood or ebony, this part is used to play notes refering to separation called “fret”. Ther are guitars with 21 frets and others with 24 frets and the closer you play from the body, the higher notes will be. You can find many forms a attachment between the body and the neck as the most common are the C and the V models. The most complex part is the pick-up. This is use to catch the vibration of the strings by a tranducer that detects the deformation of a magnetic field comming from a coil of fine wire put around a iron core. The electric current is then take to an amplifier via wires. There are many sorts of pick-ups like the one above that is called “single coil pick-up”. You can also find the “humbucker pick-up” that is used to negate the “hum” : a noisy sound comming from others electric parts of the guitar and from the ambiant environment. Finally you can install an “active pick-up” that requires a source of energy to work but negating totally the “hum” as it also have an EQ, a filters and all sorts a features in it.
Wrapping this up, it takes several parts to make a great electric guitar. You can find most of them in good companies like Fender, ESP, Dean , etc. To your culture, did you know that the biggest electric guitar ever built weights about 2.224 pounds?
References
Wikipedia, the electric guitar
http://en.wikipedia.org/wiki/Electric_guitar#Early_years
How stuff works
http://entertainment.howstuffworks.com/electric-guitar.htm