In contrast to the term topic, which refers to the subject under discussion, the term main idea refers to the point or thought being expressed. The difference between a topic and a main idea will become clearer to you if you imagine yourself overhearing a conversation in which your name is repeatedly mentioned. When you ask your friends what they were discussing, they say they were talking about you. At that point, you have the topic but not the main idea. Undoubtedly, you wouldn’t be satisfied until you learned what your friends were saying about this particular topic. You would probably pester them until you knew the main idea, until you knew, that is, exactly what they were saying about your personality, appearance, or behavior. The same principle applies to reading. The topic is seldom enough. You also need to discover the main idea.