TYPES OF BUTRESSESS

 The Flying Buttresses  is an arch, resting at one end on a detached pier and it carries the thrust of the nave vault over the aisles or cloister.
The Pier or Tower Buttresses is a simple masonry piles attached to a wall at regular intervals.
Hanging buttresses aee freestanding piers connected to a wall by corbels.
Corner buttresses are of various types such as diagonal, angle, clasping, and setback which that support intersecting walls.

Picture taken from : http://moonbeams8.blogspot.in/2009/10/art-is-trim.html

Acknowledgement: http://www.newadvent.org/cathen/03092a.htm
                              http://www.britannica.com/EBchecked/topic/86773/buttress