In physics, intensity is the power transferred per unit area, where the area is an imagined surface that is perpendicular to the direction of propagation of the energy. In the SI system, it has units watts per square metre (W/m 2).
The Ancient Greeks spoke Ancient Greek with three different major dialects: Aeolic, Doric and Ionic. They were the first Europeans to both read and write with an alphabet. This alphabet eventually led to the development of all modern European languages.
In the classical, or hellenic period, Greek existed in several major dialects, each of which has its own significance for the history of the language, but the most influential of these would ultimately prove to be the one spoken in Athens, called Attic.