Iambic pentameter is a metrical line in poetry consisting of five iambs, which are metrical feet made up of an unstressed syllable followed by a stressed syllable. This rhythmic structure is foundational to much of English poetry, particularly in the works of notable playwrights and poets, serving to create a natural flow and musical quality in language. Its frequent use in dramatic and narrative poetry helps to enhance the emotional resonance and dramatic tension within the text.