A sonnet is a poetic form that originated in Italy and is characterized by its 14-line structure. It is often written in iambic pentameter and follows a specific rhyme scheme. There are different types of sonnets, with the two most common forms being the Petrarchan (or Italian) sonnet and the Shakespearean (or English) sonnet. The Petrarchan sonnet is divided into two stanzas, an octave followed by a sestet, while the Shakespearean sonnet consists of three quatrains and a final couplet. Sonnets are known for exploring themes of love, beauty, and the passage of time