The guitar that we know today has been around for a very long time.
The orginis of the guitar relate back to Babylon, which is now Iraq. Clay plaques from 2000 B.C were located with illustrations of figures playing instruments that look like guitars. The story of the guitar is then silent for nearly 2000 years until a tomb was dug up in Rome which contained a guitar like instrument. It was constructed totally of wood and had the same structure of modern day guitars.
In the Middle Ages the guitars shape changed to include the modern day hole in its body and the fatter neck. There is a debate to whether this shape came from Germany or France.
It was in Spain that the guitar reaches its most crucial time of prgression. The Vihuela developed 12 steel frets and people began writing tablature for people to play.
The guitar well and truly moved into Europe in the 17th & 18th centuries. A lot of the European aristocracy made the guitar extremely popular created an international stage for the development of guitar playing. It is was during the 19th century that the guitar really developed the shape and modern tuning we see today. Also in that century the guitar moved out from Europe to America and the rest of the world.
The last century was where the guitar really came into its own. Guitars and the people who have played them have spanned thousands of years , and included dozens of cultures. It is a an amazing, satisfying instrument to to be able to master, with many eloquent styles.