A metaphor is a comparison between two things that are not literally alike, in order to create a deeper meaning or understanding. In poetry, metaphors are often used to create vivid imagery and to convey complex emotions or ideas. In "The Road Not Taken," Frost uses the metaphor of a fork in the road to represent the choices we make in life. The two paths represent different options or directions we can take, and the choice we make determines our future. For example, in the third stanza, Frost writes, "Oh, I kept the first for another day! Yet knowing how way leads on to way, I doubted if I should ever come back." Here, the metaphor suggests that once we make a choice, we can never go back and explore the other option.