Figures of speech are creative language expressions used to make writing more vivid, interesting, or imaginative. They go beyond the literal meanings of words to create special effects or deeper understanding. Common examples include simile (comparing two things using like or as), metaphor (a direct comparison between two unlike things), personification (giving human qualities to nonhuman things), hyperbole (intentional exaggeration), onomatopoeia (words that imitate sounds), and idioms (phrases with meanings different from their literal words).