Poetic Edda
The Poetic and Prose Eddas are ancient Norse texts containing information about the origins of the universe according to Norse mythology. Together they are thought to be the most popular and comprehensive representation of Norse mythology.
The first one collection of Old Norse poems is the most expansive source on Norse mythology. The first part of the Codex Regius preserves poems that narrate the creation and foretold destruction and rebirth of the Old Norse mythological world as well as individual myths about gods concerning Norse deities. The poems in the second part narrate legends about Norse heroes and heroines, such as Sigurd, Brynhildr and Gunnar.
The Prose Edda, sometimes referred to as the Younger Edda or Snorri's Edda, is an Icelandic manual of poetics which also contains many mythological stories. It was written by the Icelandic scholar and historian Snorri Sturluson around 1220. Its purpose was to enable Icelandic poets and readers to understand the subtleties of alliterative verse, and to grasp the mythological allusions behind the many kennings that were used in skaldic poetry.
It’s worth mentioning that the Prose Edda is not just a contemporary version of the Poetic Edda. It’s modern type of evolved mythology which integrated with Christianity.