Finding the main idea in a piece of writing is a basic reading skill. No matter what type of expository text you read, the primary comprehension goal is to identify the main idea: the most important point that the writer wants to communicate.  Main ideas are often stated toward the start of a text, usually in an introductory paragraph. They are often repeated in fuller form toward the end of a text, usually in a concluding paragraph. Main ideas may be reinforced through headings, subheadings, and other forms of emphasis. However, main ideas may also be implied and not stated directly in the text.  Sometimes you need to infer the main idea based on the details, facts, and explanations in the text.

Some texts make the task of identifying the main idea relatively easy. Articles in scholarly journals often include an abstract, which is a condensed version of the information in the article, a version which focuses on main ideas. Textbooks, articles in general interest magazines, and online articles in blogs or on websites may include headings and subheadings which make it easier to identify core concepts. All types of texts may include graphic features such as sidebars, diagrams, and charts, which help readers understand complex information and distinguish between essential and inessential points. When reading a text with these features, use them to help identify the main idea.

For texts without graphic features, headings, or abstracts, and/or for texts with implied main ideas, use the following process to identify the main idea:

1. Read the text.
2. Ask yourself: What is the text about? – What is the topic?
3. Ask yourself: What is the author saying about the topic?
4. Identify repeated concepts and language; writers often use repetition to emphasize a main idea.
5. Summarize the article after you read–put what you think the main idea is into your own words.  See if you can find any statements in the article that are similar to your summary.  If so, it’s likely that you’ve found the main idea.  If the main idea in the text is not stated but implied, then ask if your summary encapsulates the one thing you think the writer wants you to understand about the topic.

For a discussion of finding the main idea which includes examples, link to Finding the Main Idea from Monterey Peninsula College’s Writing Center.

The following two videos also provide very clear, useful discussions of finding the main idea in a text.