Metrical romances or chivalric romances are narratives telling stories that usually have a happy ending. This format of narrative poetry is written in verse or meter and can employ various poetic devices. Metrical romances may or may not involve love. However, they do commonly involve stories about a brave knight and his marvelous quests and adventures.
Some narrative poems are told in first person, otherwise known as metrical tales. An example of such a poem is "The Lady of Shallot" by Alfred Lord Tenneyson.
Much of poetry, centuries or even millenniums ago, revolved around the story of a hero and his legendary life. These poems, called epics, were first recited and passed on orally before they were finally written down and published. Epics are usually long and often describe heroic deeds as well as some events that are significant to a particular culture or nation. The Old English story "Beowulf" is an example of an epic.
Much like the name suggests, ballads were originally meant to be songs, which is why ballads follow the usual song structure. This format employs the use of quatrains or four-line verses. They usually have choruses or refrains, which are verses that are repeated throughout the poem.
Folk ballads are ballads that were created anonymously and passed down orally from generation to generation. This format of narrative poetry is usually embedded in the fabric of a culture or tradition. Folk ballads tend to not be told or recited as commonly today. The literary ballad, a similar form, is written in a way that deliberately emulates folk ballads. The difference is literary ballads are usually more complex and elaborate.