LH Paragraph IDs gives every paragraph and heading in a post or page its own id, so anyone can link straight to that part of the page rather than to the top of it. It is useful for long articles, policies and minutes, for quoting a specific passage, and for linked-data uses that need to identify part of a page.
For example, <p> becomes <p id="lh_element_id-p123-3" class="lh-paragraph-id">, and https://example.com/my-post/#lh_element_id-p123-3 opens the page at that paragraph.