The Zodiac and The Zodiac Signs

Zodiac is a coordinate system that locates twelve zones denoted as zodiac signs along the sun's ecliptic path across the heavens through twelve constellations on its way.

These same zones are known as twelve star signs, astrology signs or astrological signs, horoscope signs, birth signs and sun signs along with the original, originating either from the Greek zodiakos meaning circle of animals, or from the Sanskrit sodi meaning path (of the sun).

Extending the location coordinates to include the paths of the moon along with Mercury, Venus, Mars, Jupiter, and Saturn; an eight arc degrees band has been added to the ecliptic half above it and half below.

Astrology used these astronomical coordinates for its own purpose terming them as star signs, astrology signs or horoscope signs. Today astrology horoscopes are made based on these signs only.

There are two kinds of these location coordinates of 30 degree longitude:

Sidereal: calibrates the longitudes taking the star Aldebaran as 45 degrees and Antares as 235 degrees - movement of the sun corresponds to the constellation of the same name.
Tropical: calibrates the longitudes according to the position of the sun at the moment of the vernal equinox each year - movement of the sun corresponds to the time of the vernal equinox.