Corbels resemble a right triangle. The flat surfaces are joined to the walls or other flat surfaces, while the third and longer side is usually carved in some way, ranging from plain to extravagant.
Corbels were used as parts of castles to help hold up balconies. They did the same job when holding up extensions of the castle walls that were high up.
Most corbels that were part of castles where richly decorated. People, animals, plants and abstract designs were all carved to give the castle a unique look or to appease the royalty who had it built.
Corbel walls were used both to house the castle gutter system and to help break up the main wall and separate stories. They are a string of corbels that holds up a thin extension leading out from the castle wall.
Castles often had a number of turrets at various levels of the building. These were typically held up, at points jutting out from the wall, by corbels.