To "illustrate" means to explain or clarify a concept by providing examples, images, or diagrams. This technique helps to make complex ideas more understandable and engaging. For instance, a teacher might illustrate a scientific principle using a diagram of the water cycle to show how evaporation and condensation work. In the context of art, to illustrate often refers to creating visual representations, such as drawings or paintings, that accompany text. Children's books frequently use illustrations to enhance storytelling, making it easier for young readers to grasp the narrative and connect with the characters.