Vintage Illustration Diagram Of Columns - Greek Orders. Vintage Diagram Of Columns - Greek Orders. The Three Major Classical Orders Are Doric, Ionic, And Corinthian. The Orders Describe The Form And Decoration Of Greek And Later Roman Columns, And Continue To Be Widely Used In Architecture Today. The Doric Order Is The Simplest And Shortest, With No Decorative Foot, Vertical Fluting, And A Flared Capital.