Main Idea & Supporting Details

Main idea is the big idea or overarching concept of a piece of writing. Essentially, it is what the author wants the reader to get out of the writing, the "jist." Main idea can be found in small pieces of writing, like a paragraph, or in large pieces of writing, like an essay. The main ideas of each body paragraph should work together to help the reader understand the overall main idea of an essay.

Supporting details are details, facts, definitions, descriptions, examples, or explanations that help the reader better understand the main idea. Students often think of the supporting details as the sentences "inside the hamburger bun," hence the banner of the hamburger at the top of the page. This only addresses main idea and supporting details for single-paragraph writings, though it is a great starting point. Let's look at this analogy:

In school, when students are first taught about paragraph writing, they often learn that the topic and closing sentences of a paragraph are like the buns of the hamburger; just like the buns hold in all the yummy toppings for a hamburger, the topic and closing sentence are there to hold all the good information in. This reminds students to write topic and closing sentences that show the reader the main idea. The yummy insides of a hamburger, then, are likened to the interesting information inside the paragraph because without the interesting details, the paragraphs are boring. Likewise, the topic and concluding sentences won't hold much interest for the reader if there aren't any examples, definitions, or explanations to illustrate the main idea in the topic and closing sentences.

So... what does this have to do with main idea and supporting details? Well, just as we need to include topic and closing sentence in our writing, many authors include similar structures. Often, a writer will include a topic and/or closing sentence in their paragraphs to help show the reader what the paragraph will be about.

This same analogy could be transferred from a paragraph to an essay, then, only the sandwich we'd visualize for an essay would be much bigger! Let's look at how we can alter this analogy to fit an essay instead of a paragraph:

In this instance, the hamburger buns would be the introduction paragraph and the conclusion, which provide an overview of the essay. The introduction and the conclusion both reveal the main idea of the entire essay. The levels or "decks" of a sandwich could be the separate body paragraphs, which will each contain their own topic and closing sentences as well as the yummy stuff inside that makes hamburgers taste so good! Therefore, the main idea of the essay is in the introduction and conclusion, and the supporting details are found inside the body paragraphs.

Whether searching for the main idea in a larger text or a smaller paragraph, a passage must contain information that helps to support, prove, or show the reader more about the author's main point. Use this information to help you identify the main idea!