A couplet is a pair of lines in poetry that usually rhyme and have the same meter. This structure often conveys a complete thought or idea, making it a popular choice for poets. Couplet forms can be found in various styles of poetry, including sonnets and narrative poems. Couplets can be used to create emphasis or a memorable conclusion to a poem. Famous poets like William Shakespeare and Alexander Pope frequently employed couplets in their works, showcasing their versatility and effectiveness in expressing emotions and themes succinctly.