Rhyme scheme is the ordered pattern of rhymes at the ends of lines. It is labeled with letters: A for the first rhyme, B for the second, and so on. A quatrain rhyming ABAB means lines one and three rhyme, and lines two and four rhyme.

Different forms have different schemes. The Shakespearean sonnet rhymes ABAB CDCD EFEF GG. The Petrarchan sonnet rhymes ABBAABBA CDECDE. The limerick rhymes AABBA. Rhyme scheme is not just a technical detail. It shapes the reader’s experience. A couplet (AA) feels closed and epigrammatic. Alternating rhyme (ABAB) feels balanced. Enclosed rhyme (ABBA) feels nested. When a poem breaks its own rhyme scheme, it draws attention. That break can signal a shift in tone or meaning. Poets choose schemes deliberately, or they abandon them for free verse.

Common schemes

• Couplet: AA
• Alternating: ABAB
• Enclosed: ABBA
• Sonnet: ABAB CDCD EFEF GG