wp_summary will automagically show a summary of your post at its beginning, using h1, h2 and h3 tags to create sections.
When you write a long post, it is common to add h2 and h3 tags to create sections on a specific topic. This plug-in will search these sections and add a link to each of them at the beginning of your post. Each section will become a named anchor, allowing the user to browse quickly through your post. This summary is also understood by major search engines and should improve your CTR (click-through rate) by providing richer snippets.