The main Greek orders of architecture are Doric, Ionic, and Corinthian. The definitive form of Doric is established by the beginning of the 6th cent.
The origin of these systems is uncertain. Wooden columns similar to Doric (but with no evidence for the entablature) had been used in Aegean late bronze age architecture, but these cannot have survived to the early evolution of Doric in the 7th cent.