Hávamál ( Sayings of the high one) is presented as a single poem in the Poetic Edda, a collection of Old Norse poems from the Viking age. The poem, itself a combination of different poems, is largely gnomic, presenting advice for living, proper conduct and wisdom.
The verses are attributed to Odin. The implicit attribution to Odin facilitated the accretion of various mythological material also dealing with Odin. For the most part composed in the metre
Ljódaháttr, a metre associated with wisdom verse, Hávamál is both practical and metaphysical in content. Following the gnomic "Hávamál proper" follows the Rúnatal, an account of how Odin won the runes, and the Ljóðatal, a list of magic chants or spells. The poem was written down in the 13th century. Individual verses or stanzas nevertheless certainly date to as early as the 10th, or even the 9th century.
See wikipedia: Hávamál