In a written message, what part presents the main content on various topics?

The body of a written message is the section where the main content is presented. It elaborates on various topics, providing details, explanations, examples, and supporting information that elaborate on the purpose of the communication. In the body, the writer develops their ideas and arguments, making it essential for conveying the complete message to the audience.

In contrast, the introduction serves to introduce the topic and provide a preview, while the conclusion summarizes the points made in the body and reinforces the overall message. A summary condenses the content further, often highlighting key points without the detailed discussion found in the body. Thus, the body is distinct in its function to provide comprehensive content on multiple topics.