Before looking at what the zodiac is, it is important first to understand what the ecliptic is. If you were to imagine what you see when you look up into the sky, and if you tracked the apparent movement of the Sun through it, this is what is meant when the word ecliptic is used. Put simply it means the apparent pathway of the Sun through the sky as viewed from earth.

The zodiac is actually a group of constellations that form the backdrop to the Sun's apparent pathway through the sky that extends 9 degrees on either side of the ecliptic. The orbits of the planets (and our Moon) also fall within this zodiac belt. The word zodiac stems from the ancient Greeks - zodiakos kyklos, "circle of animals", or ta zodia, "the little animals" because most of the constellations through which the ecliptic passes represent animals. Although the constellations are irregular in size and shape the 12 astrological signs are generally allocated 30 degrees each.

"The word zodiac stems from the ancient Greeks - zodiakos kyklos, "circle of animals", or ta zodia, "the little animals..."

The ecliptic was clearly identified and divided into 12 equal signs of the zodiac around 450 BC in Mesopotamia. Most reference sources indicate that the zodiac is a Babylonian invention - the oldest record of the zodiacal signs is a cuneiform horoscope from 419 BC. At the same time, Greek sources claim the discovery of the ecliptic during the second half of the 5th century BC. Like many historical developments it is quite possible that both the Greek and Babylonian cultures developed these systems at about the same time.

Symbolically, each of the zodiac signs (Aries - Ram; Taurus - Bull; Gemini - Twins; Cancer - Crab; Leo - Lion; Virgo - Virgin; Libra - Scales; Scorpio - Scorpion; Sagittarius - Archer; Capricorn - Goat; Aquarius - Water Bearer; and Pisces - Fish) represent various qualities. For example, Aries is represented by a Ram and the qualities of initiative, bravery and assertiveness.

Because the Sun's (apparent) pathway through the heavens is basically constant and can be found at roughly the same spot for the same date in each year, this is how we came to use Sun Signs: the position of the Sun in relation to the backdrop of the zodiac constellations. This system is convenient because the average person doesn't have to have complicated planetary positions worked out to know which constellation affects them personally, the date of birth is all that is needed in most cases.