The 3 styles of classical Greek and Roman architecture are the Doric, Ionic, and Corinthian orders. These orders are most easily distinguished by their columns. To recognize their differences, it helps to be familiar with a few architectural terms. A column consists of a long shaft sitting between a base at the bottom and a capital at the top. The horizontal beam that rests on the columns is called the entablature, which is divided into 3 horizontal layers. From bottom to top, they are the architrave, the frieze, and the cornice.
Additional Vocabulary
stylobate - the platform on which the columns rest
plinth - the lowest part of the base
moldings - contoured horizontal bands that separate other architectural elements
fluting - the shallow vertical grooves that run the length of the shaft
entasis - a slight bulge in the middle of a column
necking - a molding between the top of the shaft and the bottom of the capital
echinus - the convex molding on a Doric capital
abacus - the square block at the top of the capital that supports the entablature
volute - a spiral-shaped ornament on a capital
triglyph - 3 vertical bands separated by grooves
metope - a rectangular panel, sometimes with a sculptural relief
dentils - an ornamental series of small, tooth-shaped blocks in a cornice
Image courtesy of the University of Texas at Austin
| Feature | Doric | Ionic | Corinthian |
| Overall appearance |
Simple, heavy |
Lighter and more decorative than Doric |
Most slender and ornate |
| Earliest known usage |
7th century BC |
6th century BC |
5th century BC |
| Column height to diameter ratio |
7:1 |
8:1 |
9:1 |
| Base |
No |
Yes |
Yes |
| Flutes |
20 |
24 |
24 |
| Capital |
Plain, round |
2 volutes separated by egg and dart shaped ornaments |
Elaborate, with rows of acanthus leaves below volutes |
| Entablature |
Frieze with alternating triglyphs and metopes |
Plain or sculptural frieze and dentils in the cornice |
Plain or sculptural frieze and dentils in the cornice |
Wikipedia on classical orders
Dummies.com on Doric v. Ionic v. Corinthian