The Doric order was the simplest style of column in ancient Greece. It consists of a shaft (the main structure of the column) that is 20-sided rather than cylindrical, five and a half times taller than it is wide. Doric columns have a simple capital (the decoration on top of the column) consisting of a square on top of a circle. Developed in the 7th century B.C. and popular in southern Italy, the Doric order became prominent in the 5th century B.C. for such famous buildings as the Parthenon, a temple to the Greek gods in Athens. Despite their simplicity, the Doric order appears sturdy and powerful, and is thus perfect for the columns surrounding large, rectangular buildings like the Parthenon.
The Ionic order developed later than the Doric order, around the 4th century B.C., and was more complex and decorative. Ionic columns are taller and thinner than Doric columns, with a height nine times their width. Instead of 20 sides, Ionic columns had 24 flutes (vertical lines from the top to the bottom) carved into a cylindrical shaft. While the Doric columns had no base, the bases of Ionic columns were carved to appear like a square topped with a stack of rings. The most distinctive part of the Ionic column is its capital, which consists of carved volutes (curlicues, with the appearance of a scroll or a ram's horns).
The Corinthian order was the last style of column to develop--and the most ornate. Like Ionic columns, Corinthian columns are tall, thin and fluted, although their height is 10 times their width (rather than nine for Ionic columns). The capitals are decorated with carved acanthus leaves, which had an important symbolic meaning in ancient Greece: The acanthus plant, one of the oldest in the Mediterranean, symbolized long life or immortality. Later, features of the Ionic and Corinthian styles were fused into a fourth type of Greek column, the Composite order.