Couplet poems are poems made up of two lines that usually rhyme. The two lines are usually of the same metrical length. In English poetry, meter is usually measured in syllables, and couplet lines are often either eight or ten syllables long. Couplet poems have been used in English poetry for hundreds of years, ever since rhyme became a feature of English poetry. The couplet has also been used as the basic unit, or stanza, in longer, extended poems, and also appears in other poetic forms such as the sonnet.
Writing in the 14th century, Geoffrey Chaucer may have been the first English poet to use the couplet regularly. The General Prologue to his Canterbury Tales is written in rhyming couplets, as are some of the stories in the collection. Chaucer wrote in ten-syllable lines of five accents called iambic pentameter, which became the standard meter of most couplet poems.
Couplets were sometimes used in the dramas of the late 16th century, which are better known for being written in the unrhymed form known as blank verse. In plays, Shakespeare and his contemporaries occasionally used couplets to mark the end of characters' speeches, as well as scenes and acts. Usually these were closed couplets, or two lines of text that could stand on their own as a single sentence or unit.
In the 17th and 18th centuries, rhyming couplets were often used in extended verse compositions called heroic couplet poems. The heroic couplet takes it names from being used in such epics as well as drama. John Dryden used heroic couplets in plays such as Tyrannick Love and poems including Mac Flecknoe. Alexander Pope is also often regarded as a master of the form. Significant heroic couplet poems by Pope include The Rape of the Lock and An Essay on Man.
Couplets have long been considered well suited to closing other types of poetic forms because they are so concise. The English or Shakespearean sonnet is one such example. This form begins with three four-line stanzas, each of which typically develops a thought or idea. The final couplet of the Shakespearean sonnet is called a turn, and it can summarize the poet's feelings or express an ironic take on the preceding stanzas.
Beginning in the 19th century, couplets began to fall out of favor as a poetic device. Since then, they have largely been displaced by other rhyme schemes as well as unrhymed poetry in general. Nevertheless, they remain an important form of English poetry.