A simple rhyme scheme is a type of poetic structure in which each line of the poem rhymes with the line that follows it. It is often used in traditional poetry and song lyrics, and consists of two lines that rhyme followed by two lines that rhyme. The most common example of a simple rhyme scheme is the ABBA pattern, where the first and third lines rhyme and the second and fourth lines rhyme. Another example is the ABAA pattern, where the first and fourth lines rhyme and the second and third lines rhyme.