The main idea is a sentence that provides the subject for discussion as a list of details usually supports it. If you can tell what the supporting details have in common, you can discover the main idea. You can either choose to create the main idea and details chart using complex tools or opt for EdrawMax Online that helps you create a professional-looking Main Idea and Details Chart easily and quickly. The below chart illustrates that the main idea showcases the main idea and a detailed diagram. The Main Idea and Details diagram below have individual spaces and columns for Main Idea, Details, and Summary.