The zodiac got its start thousands of years ago with Babylonian astronomers. These early astronomers looked to map the stars in the sky to create an agricultural calendar that would determine when crops should be planted and harvested based upon the natural rising and setting of particular stars and/or constellations.
Based upon the Sun's path across the sky over the course of the year — called the ecliptic — early astronomers developed an early celestial coordinate system that based latitude upon the ecliptic and longitude on the position of the Sun at the vernal equinox. They then divided the celestial sphere into 12 divisions of longitude. We call these 12 divisions the 12 signs of the zodiac.
The zodiac spread to other cultures, including the ancient Greeks and Romans. In fact, the word zodiac comes from the Greek word zoidiakos, which means “little animal sign." This makes sense since several of the signs of the zodiac are based upon animals.
Today, the zodiac is associated mainly with astrology rather than astronomy. Whereas astronomy is the scientific study of celestial objects, space and the physical universe, astrology is more of an art. Astrology can be described as a collection of beliefs and traditions that focus on how the movement of the stars and planets relate to human events on Earth