The document defines and compares two types of sonnets: Petrarchan and Shakespearean. The Petrarchan sonnet has an octave rhyme scheme of abba abba and a sestet with a variable rhyme scheme, discussing unrequited love. The Shakespearean sonnet has a rhyme scheme of abab cdcd efef gg with three quatrains and a couplet, introduced by Wyatt and Surrey to English poetry. Both use iambic pentameter.