The four classical elements of nature are: Fire, Air, Water, and Earth.
There are two QUALITIES to EACH element:
Signs which are ‘hot’ are active, enthusiastic, and extrovert. They are in motion, and changeable. They are usually people oriented.
Signs which are ‘cold’ are passive, they tend to conserve energy. Focusing on their own feelings. They are not impulsive. They take their sweet time to act on something.
Signs which are ‘wet’ are flexible, relaxed, fluid and create bonds with others. They are also very creative.
Signs which are ‘dry’ can be a little brittle. Sometimes separating and differentiating itself from others, giving the impression that it is self-centered. It is not uncommon for it to be a little tense and nervous.
The twelve zodiac signs are divided in four groups (according to the elements) called Triplicities, each containing three signs.
Aristotle – Yeah, that Greek philosopher – suggested that one element could change into another in a cyclic process just like the seasons of the year
In the same way , that system gives fluidity between the zodiac signs.
For example, the signs in winter are: Pisces, Aquarius, and Capricorn. But, Pisceans are less impulsive (cold) than Aquarians (hot). And a lot more flexible and sociable (wet), than Capricorns (dry).
I’ve prepared this short video with more information: