MOIRA

Listen, Moirai, who sit nearest of the gods to the throne of Zeus
And weave on adamantine shuttles countless and inescapable
Devices of counsels of all kinds.
Atropos, Klotho and Lakhesis, fair-armed daughters of Nyx,
Hear our prayers, you all-terrible deities of heaven and the lower world:
Greek Lyric V Anonymous Fragments 1018
Moira is the ancient Greek goddess of fate, the impersonal apportioner of destiny whose decrees not even the gods can turn aside. Moira's province is life and death, for she spins the thread of life and weaves it into the pattern of fate. She is usually portrayed as an elderly woman and her feast day was 23rd August.
Moira means 'phase' or 'lot', a part as opposed to the whole. It might refer to a plot of land, or a faction of people, or section of the zodiac. It also refers to a person's lot in life, their destiny and the good and bad luck appointed by fortune. Naturally, it also refers to the phases of the moon and the passage of time. Moira is sometimes thought of as a triple moon goddess, the daughter of Nyx ['Night']. Whether Moira was originally one, or originally three, the Greeks of the classical period thought of Moira as the Moirae or Kataklothes 'uncanny spinners of thread', sometimes shown as three women with bronze pestles and a bronze cauldron or with their traditional attributes of spindle, measuring rod and shears. They were named as Clotho ['Spinner'] the youngest who spins the thread, Lachesis ['Measurer'] who sees to it that the proper span of life is allotted to each person, carefully measuring it with her rod, and Atropos ['Inevitable'] who finally cuts the thread with her shears. Atropos is the smallest of the three, but the most feared, since she is the crone goddess of death. The city Atropatene [now Azerbaijan] was dedicated to her.
Homer referred to Moira, a single goddess, whose appearance in the Illiad usually portended some evil. In this form, she may have been an aspect of the older Aphrodite, before the patriarchal Greeks stripped her of all aspects other than love. Aphrodite is certainly referred to as the oldest of the Fates. Sometimes four fates were mentioned, but not named. The Fates also absorbed other goddesses such as Geneia and Thanate [birth and death] and Kakidike and Kallidike [good and bad luck], Aisa, the personification of destiny, Achaiva ['spinner'], and Klothes, a pre-Hellenic Goddess of spring.
The ancient Greeks believed existence to be governed by fate, a system of unfolding patterns and laws that controlled everything: men women, the natural world, and even the gods themselves. It allotted the place and function of everyone and everything: who should be rich, who should be poor, who should be a king, and who should be a slave. This moira governed the life path of everyone from cradle to grave.
The word ‘fairy’ is probably derived from the Latin for fate, fata. It is possible that the Fates were the original fairy godmothers, since they were believed to assist at the birth of certain [if not all] humans. Long after the coming of Christianity, mothers would make ready for them when a baby was due, spreading out food and gifts to ensure their favour for the child. Just as the fairies were called 'good people' in supplication, the Fates were titled Parcae, or 'merciful'. Belief in them survived in parts of Greece well into the twentieth century. Fairy godmothers dress in white [like the moon] and appear three days after the birth of a child to bless or curse it, according to the behaviour of its family. They will foretell its future, give advice and possibly favour the child with birthmarks. Once the fairy has appeared and the fate is told, it cannot be changed. Fairy godmothers also appear at marriages, and once more at death, to take the soul out of the world.
All things are subject to the will of Moira, and once she has spoken, it cannot be changed.
NB: This short article is not from my more comprehensive Goddess Encyclopaedia