Column type is a term used to describe the three main types of columns used in architecture. The Doric column type is the oldest and simplest of the three, characterized by its plain, fluted shaft and lack of a base or capital. The Ionic column type is more ornate than the Doric, featuring a base, fluted shaft, and a capital with volutes. The last type, the Ons column, is the most ornate of the three, featuring a base, fluted shaft, and a capital with volutes and an inverted bell shape.