Traditionally, a song that tells a story. Ballads are characteristically compressed, dramatic, and objective in their narrative style.
Anonymous narrative songs, usually in ballad meter. They were originally created for oral performance, often resulting in many versions of a single ballad.
The most common pattern for a ballad, consisting of four lines rimed a b c d, in which the first and third lines have four metrical feet (usually eight syllables) and the second and fourth lines have three feet (usually six syllables). Common meter, often used in hymns, is a variation rimed a b a b.
A ballad not meant for singing, written by a sophisticated poet for educated readers, rather than arising from the anonymous oral tradition.