The Prose or Younger Edda was written by the poet Snorri Sturlason and is the most detailed source we have today about the historical and mythological attitudes of the residents of Iceland in the 12th and 13th centuries. The collection of pieces was written around the year 1200 and unlike similar manuscripts of the time is not a glorification of those paving the way for Christianity but more of an entertainment piece full of the lore current and future poets would need to know. It also is the earliest known work which makes a point of trying to explain the origins of the myths from known events. Like the Poetic Edda, it is a major source of modern knowledge of Norse Mythology.
The Poetic Edda also references works which have been lost and are only known through the collection. A manuscript written around 1320 to 1330 known as the Uppsala Codex is the most important of the copies of the Edda. Its preface begins, "This book is called Edda; Snorri Sturlason wrote it in the same order in which it is set out here. The first part is about the Ćsir and Ymir, then comes the Skáldskaparmál (`Poetic Diction') and the names given to various things, last the Háttatal (`Account of Metres') which Snorri composed about King Hákon and Duke Skúli."
The complete Edda contains four parts, but the final piece, Háttatal, is not available on-line in the public domain.
The Prologue
This piece begins with classic Christian references to Adam and Eve, Noah's Arc and the early Bible tales. Working from an orthodox Christian standpoint, the prologue casts the Norse gods as heroes of old whose memories were cast aside and tarnished by those who came after them. It's explained that the gods originated in the tales of a royal family in Asia.
Gylfaginning
"The Beguiling of Gylfi" is the story of King Gylfi's inquiries about Norse Mythology to the "High One", "Just-as-high" and "Third". This presentation choice incorporates both prose and poetry and gives Snorri a great deal of leeway in his writing style and factual presentation.
Skáldskaparmál
"The Poesy of Skalds" or "Poetic Diction" is addressed to the Christian poets of the time who still wrote about the abandoned Norse gods of the olden days. It addresses the art of poetry and working with Norse Mythology as a topic, in addition to telling yet another story of a visit to Ćgir and dealings with the pantheon of gods.
Háttatal
The "Account of Metres" is a 102 stanza poem written about King Hákon and Duke Skúli with some prose accompaniment.
This translation was done by Arthur Gilchrist Brodeur and is in the public domain.
Sources:
Halvorsen, Ingrid. "Prose Edda". 3 Sep 2004: <http://www.sunnyway.com/runes/prose_edda.html>.
Hare, J.B.. "The Prose Edda". Sacred Texts. 3 Sep 2004: <http://www.sacred-texts.com/neu/pre/>.
"Introduction to the Prose Edda". 3 Sep 2004: <http://www.stavacademy.co.uk/mimir/introsnorri.htm>.