Orthodox church can vary in shape/size and layout according to the various traditions within the Church. The two most common layouts inside Orthodox churches since Justinian have been a cruciform layout, an open square/rectangular layout, or a more linear layout with side-aisles. However, the latter of which has fallen out of use since the Great Schism, as it was more widely used in Western churches and better suited the services celebrated in them than in Eastern Rite churches. The two former layouts, the open square (or rarely, circular) and the cruciform have been found best suited to celebration of the Divine Liturgy. These two interior layouts tend to be square/circular in form rather than elongated. The cruciform is the oldest of the two interior layouts and seems to be of Byzantine origin. It comes from the adaptation of two of the earliest Christian architectural forms, the basilica and the octagonal/circular form. The cruciform church often includes side-aisles similar to the Western basilica, but they are often very short and cut open in the middle, leaving a large cross shape through the middle of the church. The open square/circle is the newer of the two forms. It is most commonly found in Eastern European churches and more modern Greek churches. This church retains the earlier square/circular shape; however, the side-aisles have been removed, thus opening the space completely. This has found wider use across the world in more recent years with the invention of steel, as it allows for the dome to be supported without the need for massive arches and columns which were main features of the older cruciform churches. Iconostasis The iconostasis, also called the τεμπλον/templon, it is a screen or wall between the nave and the sanctuary, which is covered with icons. There will normally be three doors, one in the middle and one on either side. The central one is traditionally called the Beautiful Gate and is only used by the clergy. There are times when this gate is closed during the service and a curtain is drawn. The doors on either side are called the Deacons' Doors or Angel Doors as they often have depicted on them the Archangels Michael and Gabriel. These doors are used by deacons and servers to enter the sanctuary. Typically, to the right of the Beautiful Gate (as viewed from the nave) is the icon of Christ, then the icon of