Graphic organizers are visual notetaking tools that use pictures and diagrams rather than traditional outlines or lists to show relationships between ideas. They come in different shapes and sizes and can be used to organize information for various subjects like history, compare/contrast essays, and term papers by depicting things like cycles, sequences, and comparisons. The document provides examples of common graphic organizer types like clusters, tables, chains, and maps and suggests they help with comprehension by revealing patterns and connections in the information.