The < more/ >¹ tag breaks the page into two sections allowing you to create a short excerpt conveying the main idea with a button that points the user to the full article.

It is often used to simplify the main blog page where there are multiple posts and invites the user to click on the button if they want to read the full article.

An example of this technique in action is found on Charlie Arehart's blog where he summarizes nearly every blog post with the link to the full article.

If you are on the main blog page with multiple articles, click the 'Continue Reading...' button below to see this in action.

 

If you are on a page with a single post, you will not see this button. Instead, you will see the full article. This is a continuation of the article below the 'Continue Reading...' button.

¹Note: there are spaces between the opening and closing tag to avoid placing a more button where the 'more' text exists.