The wheel of the year is the annual cycle of the seasons.

 There are eight festivals throughout the year which are known as Sabbats.

The Eight Sabbats are divided into two sets of four.  These are the Grand Sabbats,
which are feminine Lunar in character and celebrate the Goddess, and the Lesser
Sabbats Solar in character and are the Equinoxes and Solstices of the Sun which
are masculine and celebrate the God.

The year is divided into a Dark and a Light half. There are two Grand Sabbats and two
Lesser Sabbats in each.

The Dark half is the Winter and the Spring, the energy of the Earth is directed inward a
time when the Earth rests before springing into new life. A time for personal contemplation
and inner workings, letting go of that which we have outgrown. 

The Light half is the Summer and Fall/Autumn the energy of the Earth is focused out
during which the fields and forests grow and produce food for the creatures of the Earth.
In the Light half, making fertility manifest in physical form.

Sabbat Dates Northern and Southern Hemisphere

The passing of time is also seen as cyclical, and is represented by a circle or wheel. The progression  of birth, life, decline and death, as experienced in human lives, is echoed in the progression of the seasons.

 Wiccans also see this cycle as echoing the life, death and rebirth of the Horned God and the fertility of the  Goddess