MB UNIUD

The lyric form of poetry which is called sonnet comes from the Italian word "sonetto" and it means "little song".

The sonnet was introduced into England by Thomas Wyatt, later than in Italy, during the Renaissance and the first writings were translation of Petrarchan sonnets.

The Italian or Petrarchan sonnet was organized into an octave and a sestet. The fist was subdivided into two quatrains in which every line rhyme with the respective line in the second quatrain; the second was subdivided into two rhyming tercet. In the octaves the poet presented a problem which was resolved in the sestets.

After that poets  arranged the compositions into a new form.
The English model consisted of three quatrains and a final rhyming couplet. In English sonnet a problem was showed; but differently from the Italian model, in the three quatrains three aspects of the same problem were presented and the final couplet gave a possible solution.

The common theme of the English sonnet was courtly love: the poets described their love, their passion for an unattainable lady, for an idealized kind of woman who looked like an angel with golden hair, blue eyes and light skin.

But Shakespeare made a parody of courtly love because he wrote about a "dark lady", a rough woman who had dark eyes and dark hair.
He wrote sonnet mainly for a fair youth and some for his rival poet.