What is the difference between a simile and a metaphor?

A simile compares things using "like" or "as," while a metaphor states one thing is another directly.

For example, "Her eyes sparkled like diamonds" is a simile—it uses "like" to make the comparison clear. In contrast, "Her eyes were diamonds" is a metaphor that directly equates the two things.

Both devices create imagery and help readers visualize descriptions, but metaphors tend to feel stronger and more immediate because they don't soften the comparison.