The sonnet is one of several forms of lyric poetry. According to the literature the sonnet entered Great Britain and It originatied in Italy in the 12th and 13th centuries. The best known Italian sonneteers were Dante and Petrarch. The sonnet  is a lyrical composition consisting of an  octave and one sestet. the octave has the function to pose the problem, the sestet tried to provide a solution.

The first English sonneteer, Thomas Wyatt tried to translate the Petrarchan sonnet  but there were some metrical problems. In the Italian sonnet rhytm is given by the length of the syllabus, on the other hand english rhytm depends on the alternation of stressed and unstressed words. So there was the necessity of arranging in another way the Italian sonnet; in this way born The Shakespearean or Elizabethan sonnet; it characteristically embodies four divisions: three quatrains and a rhymed couplet.

Shall I compare thee to a summer's day?

Thou art more lovely and more temperate:

Rough winds do shake the darling buds of May,

And summer's lease hath all too short a date,

Sometime too hot the eye of heaven shines,

And often is his gold complexion dimmed,

And every fair from fair sometime declines,

By chance, or nature's changing course, untrimmed.

But thy eternal summer shall not fade,

Nor lose possession of that fair thou ow'st,

Nor shall death brag thou wand'rest in his shade,

When in eternal lines to time thou grow'st.

So long as men can breathe or eyes can see,

So long lives this, and this gives life to thee.

 This is the 18^th sonnet of shakespeare called “ Shall I compare thee to a summer’s day?” and it is one of the most famous sonnet.        

It is a comparison between the “ Fair Youth” and a summer’s day. The fair youth might be a man. The poem starts with a line of adoration to the beloved—"Shall I compare thee to a summer's day?" The beloved is both "more lovely and more temperate" than a summer's day. The speaker lists some negative things about summer: it is short—"summer's lease hath all too short a date"—and sometimes the sun is too hot—"Sometime too hot the eye of heaven shines." The summer's day is found to be lacking in so many respects (too short, too hot, too rough, sometimes too dingy),

the “Fair Youth “is like a summer's day at its best, fair, warm, sunny, temperate, one of the darling buds of May, and that all his beauty has been wonderfully highlighted by the comparison.However, the beloved has beauty that will last forever, unlike the fleeting beauty of a summer's day. By putting his love's beauty into the form of poetry, the poet is preserving it forever. "So long as men can breathe, or eyes can see, So long lives this, and this gives life to thee." The lover's beauty will live on, through the poem which will last as long as it can be read.