The guitar is one of the most widely known stringed instruments in the world

The guitar dates all the way back to the 15th century

There are a lot of types of guitars, but mostly they can be boiled down into two categories:
The acoustic guitar

And the Electric guitar

The acoustic guitar does not need to be amplified and is mostly known for its use in folk or country music
The electric guitar does need to be amplified and is mostly known for its use in rock and roll