Each element has unique quality of supporting or creating another element, as well as the quality of weakening or destroying yet another element.
Such as water can put out fire (destruction) and can make wood grow (creation), the wood is then burned to create fire and fire reduces to ash thus settling into the earth, and so on.
To be more complete: metal will create water, water will create wood, wood will create fire, fire will create earth and earth will then create metal.
However, there are also a cycle of incompatibility (destruction): metal will destroy wood, wood will destroy the earth, earth will destroy water, water will destroy fire and fire will then destroy the metal.
In Chinese astrology there are no strongest or most powerful element, every element is equally important and powerful.
In the study of Chinese Calender Science, those five elements were weighted for their weakness and strength during each of the four seasons.
Fire is the strongest in summer, wood is the strongest in spring, earth will be the strongest during the season transitions, and so forth.
Each of these elements also has its characteristics, strength and even compatibility with other elements.
The five elements and their relationship or interaction with one another is the fundamental part used in Chinese philosophy and astrology.
In the olden days, these elements were linked with five planets; Jupiter for Wood, Saturn for Earth, Mars for Fire, Mercury for Water and Venus for Metal.
Astrologers need to find out the positions of those planets to know what are the issues which will dominate a person in her or his life.
The Chinese five elements are also linked with particular colors.
For example green is associated with wood, brown with the earth, red with fire, white with metal and black with the water.
These elements are also linked with Chinese zodiac animals.
Fire is associated with the Snake, Horse and the Sheep.
Wood is associated with the Rabbit, Tiger and the Dragon.
Metal is linked with the Monkey, Rooster and the Dog.
Water is linked with the Pig, Rat and the Ox.
To be more detailed, the five elements can also be applied not only to the colors, seasons and zodiac animals but also to the directions, sounds, hours, days, months and years.