Definition: When you compare to different things.
Example: Shall I Compare Thee To A Summer's Day
Sonnet 18
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.
William Shakespeare
Significance: We use metaphor to compare to things together in an indirectly way. It will make the readers think more and attract the readers better.