what is the main concept of astrology?

Astrology is the study of the movements and relative positions of celestial objects as a means for divining information about human affairs and terrestrial events.Astrology has been dated to at least the 2nd millennium BCE, and has its roots in calendrical systems used to predict seasonal shifts and to interpret celestial cycles as signs of divine communications. Many cultures have attached importance to astronomical events, and some – such as the Indians, Chinese, and Maya – developed elaborate systems for predicting terrestrial events from celestial observations.