There are two basic types of sonnets, the older, Petrarchan form and the more familiar Shakespearean sonnet. While both types of sonnets contain 14 lines, those lines are grouped differently, and the sonnet rhyme schemes are also different. Where the Petrarchan, or Italian, sonnet arranges itself into two stanzas, the Shakespearean, or English sonnet, is organized into four.
Both types of sonnets are written in iambic pentameter, which means each line contains five beats with every other syllable stressed. The Italian sonnet divides those lines into a group of eight and a group of six. The sonnet rhyme schemes in the first stanza are traditionally found with the first, fourth, fifth, and eight lines rhyming with one another and the second, third, six, and seventh lines carrying a second rhyme. If the first set of rhymes is called A and the second set called B, the rhyme scheme is visually represented as ABBAABBA.
The second stanza contains six lines, and there are a number of accepted variations to the three new rhymes that are introduced. If those rhymes are represented by letters C, D, and E, the sonnet rhyme schemes they make can appear in a number of ways. The first two lines, the second two lines, and the third two lines can each rhyme as CC, DD, and EE. Alternatively, the rhymes can be spread throughout the six lines, such as CDECDE or CDEEDC. Other arrangements are occasionally used, such as CDCEDE or even EDCDEC, which contain the rhymed words but don’t place them into a pattern of lines.
In contrast, the English sonnet is arranged into three stanzas containing four lines each along with a two-line rhyming couplet. As with the Italian sonnet, each line is given five beats, or meters; this is called pentameter. Traditionally, the lines are broken into iambic beats, which stress the second, fourth, sixth, eighth, and tenth syllables.
The English sonnet allows a greater number of rhyming pairs in the poem, which means the poet is less restricted as to word choice and, ultimately, the way the subject of the poem unfolds. Every other line unfolds throughout the poem, but each new stanza is an opportunity for a new rhyming pair. Thus, English sonnet rhyme schemes can be written as ABAB CDCD EFEF GG, with the final rhyme found in the rhyming couplet that sums up the poem’s theme, which typically offers a twist or deeper meaning.