The Norns (Old Norse: norn, plural: nornir) in Norse mythology are female beings who rule the destiny of gods and men, a kind of dísir comparable to the Fates in Greek mythology.
According to Snorri Sturluson's interpretation of the Völuspá, the three most important norns, Urðr (Wyrd), Verðandi and Skuld come out from a hall standing at the Well of Urðr (well of fate) and they draw water from the well and take sand that lies around it, which they pour over Yggdrasill so that its branches will not rot. These norns are described as three powerful maiden giantesses (Jotuns) whose arrival from Jötunheimr ended the golden age of the gods. They may be the same as the maidens of Mögþrasir who are described in Vafþrúðnismál (see below).
Beside these three norns, there are many other norns who arrive when a person is born in order to determine his or her future. There were both malevolent and benevolent norns, and the former caused all the malevolent and tragic events in the world while the latter were kind and protective goddesses. Recent research has discussed the relation between the myths associated with norns and valkyries and the actual travelling Völvas (seiðr-workers), women who visited newborn children in the pre-Christian Norse societies.
Read more about Norns: Etymology, Relation To Other Germanic Female Deities, Attestations