Each sign is associated one of the classical elements (water, fire, earth and air.) Fire and Air signs are considered positive or extrovert, masculine signs; while Water and Earth signs are considered negative, introvert, feminine signs.
- Fire signs (Aries, Leo, and Sagittarius)
- Earth signs (Taurus, Virgo, and Capricorn)
- Air signs (Gemini, Libra, and Aquarius)
- Water signs (Cancer, Scorpio, and Pisces)
And below is the explanation of each of the elements that I found via Zodiac-Astrology-Signs.com