A rhyming scheme, also known as a rhyme scheme, refers to the pattern of rhymes at the end of each line in a poem or song. It is represented using letters to indicate different rhyme sounds. For example, in a poem with an ABAB rhyme scheme, the first and third lines rhyme with each other (A), and the second and fourth lines rhyme with each other (B). Rhyme schemes can vary and be more complex, such as AABB, ABBA, or even more intricate patterns. They are used to create a sense of rhythm, structure, and musicality in poetry and lyrics.