NOTE: The Yearly Calendar is kind of unusual because it has a pagan or wiccan feel instead of a Christian feel. I'll try to explain words when they pop up. Not all will be understood immediately.
The Calendar is truly called The Wheel of the Year. It is an annual cycle of seasonal festivals observed by pagans and wiccans as well as the most important, The Family of Ancient Power. Each festival marks the year's chief solar events (solstices and equinoxes).
Four of them are called "quarter days". Each one of these is a major festival. The other four are called "cross-quarter days". And these are minor festivals.
Each festival is called a "spoke" or a sabbat.
Sabbats of The Wheel of the Year
Yule/Midwinter
Yule is when all Winter/Ice/Snow deities bring us Winter. As all shall live, all shall die. And this cycle reminds us of the Circle of Life. Yule is one of the Four Great Sabbats as it is one of the most powerful as it is a solstice.
Father Winter carries the task of guiding all Winter Deities to bring Winter to Earth officially.
Imbolc
Imbolc is the traditional mark for the first stirrings of spring. It is dedicated to the goddess Brigid, daughter of The Dagda and one of the Tuatha Dé Danann.
Although spring truly begins on Ostara, the Earth begins to awaken in early February.
Ostara
Named for Ēostre, an Anglo-Saxon Goddess of New Beginnings, this midpoint between Imbolc and Beltane is the second of three spring celebrations. The holiday of Ostara is when plants and animals emerge from the grips of winter.
Beltane
Beltane lies about midway between the spring equinox and summer solstice. It is the unofficial start of summer.
Litha/Midsummer
Litha is the Sabbat of Magic and one of the four greats. While there are seasonal ceremonies beside Winter, they have nothing to do with mystical world's people and places.
All Guardians take their place and return some Magic back into the planet. The leaders also go with them.
Lughnasadh
Termed as Lughnasa or Lúnasa is a Gaelic festival marking the beginning of the harvest season. It is one of four Gaelic seasonal festivals that is was widely observed throughout Ireland, Scotland and the Isle of Man. It is about halfway between the summer solstice and autumn equinox.
The festival is named after the god Lugh.
Mabon
Mabon is a neopagan festival of thanksgiving for the fruits of the earth and a recognition of the need to share them to secure the blessings of the Goddess and the Gods during the coming winter months. The festival is generally considered to be a feast-centered holiday. It lies in the middle between Lughnasa and Samhain.
Samhain
Samhain is one of The Four Lesser Sabbats. For Wiccans, Samhain is a time to celebrate the lives of those who have passed on, and it often involves paying respect to ancestors, friends, pets who have died. It is seen as a festival of darkness, which is balanced at the opposite point of the Wheel by the festival of Beltane, which is celebrated as a festival of light and fertility. Many neopagans believe that the veil between this world and the afterlife is at its thinnest point of the year at Samhain, making it easier to communicate with those who have departed.