ZodiaziThe Five Elements
Wood, Fire, Earth, Metal and Water are phases of change. The element of a year comes from its Heavenly Stem and adds a second layer to the animal.
Wood 
Fire 
Earth 
Metal 
Water The Five Elements (五行) describe five phases of change: Wood, Fire, Earth, Metal and Water. They are not chemical elements but stages of a process, which is why some translators prefer Five Phases.
Two cycles
In the generating cycle (生) each phase feeds the next: Wood feeds Fire, Fire creates Earth, Earth bears Metal, Metal enriches Water and Water nourishes Wood. In the controlling cycle (克) each phase restrains another: Wood breaks up Earth, Earth dams Water, Water puts out Fire, Fire melts Metal and Metal cuts Wood.
The element of your year
Every year has a Heavenly Stem, and each pair of stems belongs to one element, one yang and one yin. That is why element years come in twos: 2024 and 2025 were Wood, 2026 and 2027 are Fire.
Year element and the BaZi chart
The element of the birth year is only one of eight characters in a full BaZi chart, which also looks at the month, day and hour. On Zodiazi the element always means the element of the year unless the page says otherwise.