Which element of writing gives readers an idea of the overarching message or purpose?

The main idea serves as the foundation of a written work, encapsulating the overarching message or purpose that the author intends to communicate. It synthesizes the primary thoughts and themes of the text, guiding the reader's understanding of what the author is trying to convey. By presenting the main idea, writers provide a clear focus for their audience, allowing them to grasp the essential point of the writing.

In contrast, the topic merely identifies the subject matter, but it does not convey the specific message or insight intended by the author. Supporting details provide evidence and elaboration for the main idea, but they do not encapsulate the overall message by themselves. A summary sentence, while useful for recapping key points, typically reflects information already presented rather than articulating the primary message succinctly. Therefore, the main idea distinctly highlights the central theme or intent of the text.