What is it about the guitar that makes it fundamental to rock and folk music?

It's the easiest instrument to learn.

the sound that just hits your nuts.

the quality of sound, and it is fun to play!

and to transport.

dude! what, are you gonna play a flute instead.
thats like kenny g or something

Its cheap, versatile, and sexy!

^ what he said

It's easy to sustain notes.

Hah! You try writing Stairway to Heaven on a french horn or something! What an obvious question,
The guitar fills alot of space sonically, you look cool when you play, and it lends it self to songwriting because you dont need your mouth to play,
the only instrument that could fill the void of a guitar is a piano,
and thats gay..

lol guitar? its not,
to have a band, you only need a drummer and a bass guitarist, drummer keeps the rythem and bass player keeps the rythem and the tune. Guitarists are over-glorified lol and there only there to look flashy

It's the most meaty part of the songs, and has the most versatility