Western astrology is the system of astrology

Astrology

Astrology consists of a number of belief systems which hold that there is a relationship between astronomical phenomena and events in the human world...

 most popular in Western countries. Western astrology is historically based on Ptolemy

Ptolemy

Claudius Ptolemy , was a Roman citizen of Egypt who wrote in Greek. He was a mathematician, astronomer, geographer, astrologer, and poet of a single epigram in the Greek Anthology. He lived in Egypt under Roman rule, and is believed to have been born in the town of Ptolemais Hermiou in the...

's Tetrabiblos

Tetrabiblos

The Tetrabiblos , also known under the Latin title Quadripartitum , is a text on the philosophy and practice of astrology, written in the second century AD by the Alexandrian scholar Claudius Ptolemy ....

 (2nd century AD), which in turn was a continuation of Hellenistic

Hellenistic astrology

Hellenistic astrology is a tradition of horoscopic astrology that was developed and practiced in Hellenistic Egypt and the Mediterranean, whose texts were written in Greek , mainly around the late 2nd or early 1st century B.C.E...

 and ultimately Babylonian

Babylonian astrology

In Babylon as well as in Assyria as a direct offshoot of Babylonian culture, astrology takes its place in theofficial cult as one of the two chief means at the disposal of the priests for ascertaining the will and intention of the gods, the other being through the inspection of the liver of the...

 traditions.

Western astrology is largely horoscopic

Horoscopic astrology

Horoscopic astrology is a form of astrology that uses a horoscope, a visual representation of the heavens, for a specific moment in time in order to interpret the inherent meaning underlying the alignment of the planets at that moment...

, that is, it is a form of divination

Divination

Divination is the attempt to gain insight into a question or situation by way of an occultic standardized process or ritual...

 based on the construction of a horoscope

Horoscope

In astrology, a horoscope is a chart or diagram representing the positions of the Sun, Moon, planets, the astrological aspects, and sensitive angles at the time of an event, such as the moment of a person's birth. The word horoscope is derived from Greek words meaning "a look at the hours" In...

 for an exact moment, such as a person's birth, in which various cosmic bodies are said to have an influence.
Astrology in western popular culture

Popular culture

Popular culture is the totality of ideas, perspectives, attitudes, memes, images and other phenomena that are deemed preferred per an informal consensus within the mainstream of a given culture, especially Western culture of the early to mid 20th century and the emerging global mainstream of the...

 is often reduced to sun sign astrology

Sun sign astrology

Sun sign astrology is the form of astrology most commonly found in many newspaper and magazine columns. It is a simplified system of astrology which considers only the position of the Sun, which is said to be placed within one of the twelve zodiac signs depending on the month of birth...

, which considers only the individual's date of birth (i.e.