Definition:
Have no rules
Can rhyme
Don't have to rhyme
"Modern" poetry
Any length or style
After the Sea-Ship—after the whistling winds;
After the white-gray sails, taut to their spars and ropes,
Below, a myriad, myriad waves, hastening, lifting up their necks,
Tending in ceaseless flow toward the track of the ship:
Waves of the ocean, bubbling and gurgling, blithely prying,
Waves, undulating waves—liquid, uneven, emulous waves,
Toward that whirling current, laughing and buoyant, with curves,
Where the great Vessel, sailing and tacking, displaced the surface;
The fog comes
on little cat feet.
It sits looking
over harbor and city
on silent haunches
and then moves on.