An iambic foot is the iambic meter's basic metric unit. It consists of two syllables, an unstressed and a stressed one. The rhythm of an iambic foot sounds like this: da-DUM.
When four iambic feet are put together, forming a poetic line, the meter is called iambic tetrameter. It follows the rhythm da-DUM da-DUM da-DUM da-DUM, where "da" is the unstressed syllable and "DUM" is the stressed one.
When five iambic feet are put together to form a line, but the poet follows no specific rhyme pattern, the meter is called iambic pentameter, or blank verse. Iambic pentameter is the most popular type of iambic meter. It follows the rhythm da-DUM da-DUM da-DUM da-DUM da-DUM.
Iambic meter is a popular meter in poetry, and iambic pentameter is the most-used form. The author who is most widely associated with this meter is William Shakespeare, who wrote most of his sonnets and many of his plays in iambic meter. Studying iambic pentameter helps readers to better understand the structure of Shakespeare's works.