Nagara, Dravida and Vesara are three distinct styles of temple architecture that developed in different parts of India. The Nagara style is primarily found in northern India, while the Dravida style is predominant in southern India. The Vesara style, also known as the Chalukya style, developed in the Deccan region.
The Nagara style is characterized by a curvilinear shikhara or tower, which is divided into several sections by projecting moldings and is topped by an amalaka or a ribbed stone disc. The main hall of the temple is square in plan and is surrounded by an ambulatory path. The Dravida style, on the other hand, is characterized by a pyramidal tower or vimana that is composed of several tiers or talas, each with a distinct roof.
The Vesara style is a fusion of the Nagara and Dravida styles and is characterized by a tower that combines the features of both styles. The vesara tower typically has a curved profile, like the Nagara style, but has multiple tiers, like the Dravida style. The main hall of the temple is rectangular in plan and is surrounded by subsidiary shrines.
Each style has its own unique features and has contributed to the rich diversity of temple architecture in India.