HiFi is a head and foot injection plugin. It allows you to inject code into the head and foot areas of your posts and pages on a per-page basis.
HiFi adds a "Head & Foot" meta box when editing a post or page. It basically allows you to inject
<meta> and any other code you want into the head and foot areas of your posts and pages. The code injected is page-specific, this means that only the pages you want code inserted into will be affected.