Textual aids are educational tools that provide support and facilitate understanding of a text. They include highlighting, bolding, or italicizing important words, and adding charts, diagrams, graphs or images. Graphic organizers visually represent ideas, concepts and relationships. Common types include idea wheels, Venn diagrams, tree charts, organizational charts, sequence of events chains, cause-and-effect maps, timelines, concept maps, mind maps, and flowcharts. Story maps use graphic organizers to help students learn the elements of a book.