Not all music requires drums though, Bluegrass uses Banjo to get its percussion sounds.

Wow, I forgot about "The National Anthem," great example and there's other Radiohead examples also. But yeah it's hard to think of them like I said, which I guess sorta makes the guitar the most important? This question is more about your definition of importance I feel.

Well, no one ever said that all music needs a guitar, its just the trendy instrument these days.

Its still replacable, you could choose any other kind of lead or rhythm instrument to take its place, it just produces a different sound.

Theres a lot of different and creative things that folks today could do musically, but they choose not to, and they follow the quarter centurys old guitar/bass/drums trend instead.

Is trend the right word here? The definition of being rock is partly comprised of usually (more often that not) using a guitar in your music.

The role of guitars in rock grew noticably in the 60s because of players like Hendrix, Clapton, Beck, Santana, Page, Townshend, etc who helped raise the bar for true virtuosity of the instrument in the realm of rock music... Rock n roll wasnt always based strictly around guitars, just ask Little Richard, Jerry Lew Lewis and Fats Domino.

The role of the guitar has nothing to do with anything. From the blues, RNB, rock 'n' roll, Chuck Berry, etc spawned the creation of rock because people liked the way it sounded and so the commercialism grew. Others' copied and decided to take the rock elements and strand it into a wider variety of music, but obviously still encompassing rock because of the instruments. Rock = guitar/bass/drums/vocals. It's just a formula that worked. It wasn't "based" around guitars, per say, it was just a combination of instruments working together for the audiences interest.

Rubbish, tell that to Jerry Lee.

But he's rock 'n' roll.

i go with guitar..

a guitar sounds amazing alone as does a persons voice.. (if a person can sing or play well i mean)

but to me i really love the sound of guitar so thats why i go with that.

I voted drums with anything percussive in mind. I mean, the drums are like the heartbeat of the band. I play the guitar, personally, but I think that my own songs are nothing without a beat. Even folk songs with just acoustic and such still have something percussive with them a lot of times like tambourine.