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1. WordPress Plugin Displays the Type of Document, is_page, is_single …

   … is_feed, is_home, is_month, is_page, is_plugin_page, is_preview, is_robots, is_search, is_single, is_singular, is_time, is_trackback, is_year, is_404. … wordpress/what-is-this-plugin.html

2. Plugins are tools to extend the functionality of WordPress

   It shows a semi-transparent box on the document you are viewing that tells you if its a page, single, feed, category, etc.. Related · is_trackback · RDF … wordpress-plugins/

3. SEO Boost from 404 Plugin? Focus on humans

   function redirect_canonical($requested_url=NULL, $do_redirect=true) { global $wp_rewrite, $posts, $is_IIS; if ( is_feed() || is_404() || is_trackback() … seo/404-google-wordpress-plugin.html