Is the typical
steel-string guitar. There are actually many varities of them, but the Dreadnaught has become the most popular. It is what you see most rock-stars playing, that is those that play acoustic.
Dave Matthews is a prime example. The Dreadnaught is big bulky and full of noise. Whether a guitarits is
struming or
picking the guitar will produce a nice full sound. Even some
finger style or
classical guitar players will play on a Dreadnaught. Basically the be all do all of acoustic guitars.