Form entities name the specific structural patterns a literary work, especially a poem, can take: a fixed rhyme scheme, a line count, a metrical convention or a broader shape such as the sonnet, the ghazal or an extended prose form. Eight bands group this atlas's form roster by tradition and structure, Sonnet Forms, Fixed Forms of the Romance Tradition, East Asian Verse Forms, Middle Eastern and Persian Verse Forms, Narrative and Song Forms, Short Lyric and Epigrammatic Forms, Open and Experimental Verse, and Extended Prose Forms. A form is a structural vocabulary, distinct from the thematic genre a work also carries.