A Latin cross or crux immissa is a type of cross in which the vertical beam sticks above the crossbeam, with the three upper arms either equally long or with the vertical topmost arm shorter than the two horizontal arms, and always with a much longer bottom arm.
In the USA, the Latin cross began as a Roman Catholic emblem, being vehemently contested as Satanic by various Protestant denominations in the 19th century, but has since become a universal symbol of Christianity and is now the main representation of the cross for Protestants, too.
A Latin cross plan is a floor plan found in many churches and cathedrals. When looked at from above or in plan view it takes the shape of a Latin cross (crux immissa). Such cruciform churches were very common in the West during the Romanesque period. The Latin cross plans have a nave with aisles or chapels, or both, and a transept that forms the arms of the cross. It also has at least one apse that traditionally faces east. Many also have a narthex at the entry.