Acoustic guitars are often described rather carelessly. For example, the terms dreadnought and jumbo are often used interchangeably, and flat top is usually applied to dreadnoughts, but in fact means anything that is not an archtop! Lets try to disentangle this mess .
This is probably the shape that most players would identify as the typical acoustic. Aptly named after a class of battleship, the dreadnought is the general-purpose workhorse acoustic guitar for both strumming and picking. The body shape is much squarer than the classical guitar and other types of acoustic, and there is sometimes a very slight angle between the top and the back, making the guitar deeper at the endpin than at the heel. This helps to iron out the resonant frequencies that can plague acoustic instruments. The dreadnought shape was developed by C.F. Martin & Co. and is still associated with their name.