The Expand Comments Plugin provides Wordpress with the ability to expand the comments of a post below to any point on a page using AJAX. What this means, is that a user can click the "Expand Comments" link, and have the comments be added to the page, no refresh required. The "flow" of the site is not changed (the user can stay on the main blog page) as well as provides a streamlined feel to the blog.

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Expand Comments, WordPress, Plugin