Sonnets are 14 line poems with a strict structure, typically featuring a personal or passionate topic. They are divided into an 8 line octave presenting a problem or situation, followed by a 6 line sestet addressing the issue, often with a concluding couplet. Between these sections is a volta, or tonal shift, to transition between introducing the topic in the octave and resolving it in the sestet. Shakespeare was a master of the sonnet form.