1.   The central dome is raised on squinches above the wide pointed crossing arches.

2.   Inside, the nave vaults are octagonal domical shape and the central dome is carried on pseudo-pendentives rather like squinches.

3.   Generally the central dome which represented the vault of heaven was covered with a picture of Christ Pantocrator surrounded by angels and His apostles.

4.   The domed basilica where there is a central dome with an extension on the long axis into two semi-domes, e.g. Santa Sophia, Istanbul.

5.   There is a central dome rising on a drum which has a cylindrical interior and polygonal exterior.