Final answer:
In architecture, ribs are arches that form a vaulted ceiling, extending from masonry projections called springing, and are crucial in supporting the structure and aesthetic of Gothic buildings.
Step-by-step explanation:
The ribs, in an architectural context, refer to the series of arches that form the framework of a vaulted ceiling. These ribs originate from masonry projections which are known as springing or springers. The purpose of these ribs is to provide structural support to the ceiling, distributing the weight of the roof and facilitating the construction of more elaborate and higher ceilings.
Ribs are a common feature in Gothic architecture, where they enabled builders to create impressive and towering structures. Gothic ribbed vaults often used pointed arches, which provided the advantage of directing more of the weight vertically downwards rather than outwards, thus allowing for greater heights to be achieved while using thinner wall structures.
Rib vaults can be decorated with intricate patterns and are supported at intervals by thin columns, enhancing the sense of verticality and open space within the building. This is evident in several historical buildings where the use of ribbed vaults contributes to the elegance and grandeur of the interior space.