The term Blank verse means poetry that does not use rhyme.
Blank verse relies on the meter of the lines in the poem to give structure, and to create the feeling of poetry as compared to prose. An example from William Wordsworth's poem Michael shows the lack of rhyme and the strict meter in blank verse – each line sticks fairly closely to the pattern of iambic pentameter:
Many critics judge blank verse to be better than rhyme for serious subjects, and many poets have used blank verse for their most important works. Shakespeare used rhyme in his early plays, but in his more mature works like Hamlet he preferred blank verse. John Milton wrote Paradise Lost in blank verse, including a note at the beginning of the poem saying that rhyming poetry was used to disguise badly written poems, Lord Tennyson used it for Idylles of the King, and Wordsworth used it for The Prelude and The Excursion. John Keats used rhyme in his Endymion, his first try at a major poem; for his second attempt, Hyperion, he switched to blank verse. The longest poems in English literature are written in blank verse, for example The Fall of Nineveh by Edwin Atherstone or King Alfred by John Fitchett. This last is about 130 000 lines long.[1]
Many 20th century poets gave up both rhyme and the strict meter of blank verse to write free verse.