A sonnet is a fourteen-line lyric poem, customarily written in iambic pentameter. The sonnet form first became favored throughout the Italian Renaissance when the poet Petrarch published a progression of love sonnets addressed to an idealized woman named Laura.
The sonnet extended throughout Europe to England, where after it's initial renaissance "Petrarchan” form had many revivals and periods of renewed interests. The sonnet was the form of choice for lyric poets, particularly lyric poets, seeking to engage with traditional themes of love and romance. Sonnets were also written throughout the height of classical English verse.
The sonnet remains popular. Sonnets first became notable during the 14th century when the form used by Petrarch became significant in Italy. The style spread during the Renaissance to England, Portugal, Spain, and France.