Graphic and visual aids are used to summarize information for readers. They include graphs, diagrams, charts, tables and other pictorial forms that consolidate and clarify written material. Visual aids allow complex ideas to be explained concretely and abstract concepts to be visualized. They can also present new information alongside text. Effective interpretation of visual aids involves understanding what is being measured, looking for trends or patterns, and drawing important conclusions. Common types are line graphs, bar graphs, pie charts, organizational charts, flowcharts, diagrams and tables.