Shakespearean sonnet The variation of the sonnet form that Shakespeare used—comprised of three quatrains and a concluding couplet, rhyming abab cdcd efef gg—is called the English or Shakespearean sonnet form, although others had used it before him. This different sonnet structure allows for more space to be devoted to the buildup of a subject or problem than the Italian/Petrarchan form …
https://www.poetryfoundation.org/learn/glossary-terms/shakespearean-sonnet

