Comparing two unlike things using like or as?

Comparing two unlike things using "like" or "as" is known as a simile. For example, saying "Her smile was like sunshine" illustrates the warmth and brightness of her smile by comparing it to the sun. This literary device enhances imagery and helps readers understand emotions or qualities in a vivid way. Similes are effective in creating connections between dissimilar concepts, making descriptions more relatable and impactful.