Types of verse
Blank verse is poetry written in regular, metrical, but unrhymed, lines, almost always composed of iambic pentameters.
Of Man's first disobedience, and the fruit
Of that forbidden tree, whose mortal taste
Brought death into the World, and all our woe,
With loss of Eden, 'till one greater Man
Free verse is usually defined as having no fixed meter and no end rhyme. Although free verse may include end rhyme, it commonly does not.
Whirl up, sea—
Whirl your pointed pines,
Splash your great pines
On our rocks,
Hurl your green over us,
Cover us with your pools of fir.
- Wiktionary, "Verse" (accessed 8 August 2014).