3 terms

Poetry: The Sonnet

Kennedy, X. J., and Dana Gioia. Literature: an introduction to fiction, poetry, drama, and writing. Interactive ed., 11th ed. New York: Longman, 2010. Print.
A fixed form of fourteen lines, traditionally written in iambic pentameter and rimed throughout.
Italian sonnet
Also called Petrarchan sonnet, it rimes the octave (the first eight lines) a b b a a b b a; the sestet (the last six lines) may follow any rime pattern, as long as it does not end in a couplet. The poem traditionally turns, or shifts in mood or tone, after the octave.
English sonnet
Also called Shakespearean sonnet, it has the following rime scheme organized into three quatrains and a concluding couplet: a b a b c d c d e f e f g g. The poem may turn-that is, shift in mood or tone-between any of the rime clusters.