Capricorn, Aquarius, Pisces, Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius,Ophiuchus; Ophiochus was a snake-bearer; the new one got added in cause earth's orbital plane tilts just a little bit, and over the past 400 years since the zodiacs were declared, the orbital plane of the earth has tilted just slightly enough that the sun now passes through the constellation Ophiochus, making it a new birthsign, A new one will not be added, and none of the old ones will be taken away for atleast a few tens of thousands of years
The astrological signs are Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces. They are twelve in number. They are also called the twelve 30 degree sectors of the ecliptic. For more information, check out http://en.wikipedia.org/wiki/Astrological_sign.