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Global Variables

Introduction

WordPress-specific global variables are used throughout WordPress code for various reasons. Almost all data that WordPress generates can be found in a global variable, which makes them very handy and important for developers.

To access a global variable in your code, you first need to globalize the variable with global $variable;

General Settings

$wp_did_header (boolean) Whether WordPress has been instantiated yet
$table_prefix (string) The MySQL table prefix for the WordPress install (default: 'wp_')
$wp_version (string) The installed version of WordPress
$wp_db_version (int) The version number of the database
$tinymce_version (string) The installed version of TinyMCE
$manifest_version (string) The cache manifest version
$required_php_version (string) The version of PHP this install of WordPress requires
$required_mysql_version (string) The version of MySQL this install of WordPress requires
$blog_id (int) The ID of the blog. (Will be 1 unless Multisite is enabled)
$PHP_SELF
$timestart (float) PHP 4 standard microtime start capture.

$wpdb The global instance of the Class_Reference/wpdb class.
$_wp_using_ext_object_cache (boolean) If an object-cache.php file exists in the wp-content directory, it uses that drop-in as an external object cache.
$wp_object_cache The global instance of the Class_Reference/WP_Object_Cache class.
$wp_filter (array) A multi-dimensional array of all functions that have been added to filters/hooks.
$merged_filters
$wp_current_filter (array) Stores the list of current filters with the current one last.
$allowedposttags (array) Stores HTML elements that are allowed in a post's content.
$allowedtags (array) Stores HTML elements that are allowed in a post's title and comments.
$allowedentitynames (array) Stores HTML entities that are allowed in a post.
$current_site (NULL) Deprecated as of 3.2.1
$current_blog (NULL) Deprecated as of 3.2.1
$shortcode_tags (array) Stores a list of all registered shortcodes.
$wp_embed The global instance of the WP_Embed class.
$wp_registered_sidebars (array) Stores a multi-dimensional array of all registered sidebars and related details.
$wp_registered_widgets (array) Stores a multi-dimensional array of all registered widgets and related details.
$wp_registered_widget_controls (array) Stores the registered widget control options.
$wp_registered_widget_updates private global.
$_wp_sidebars_widgets private global.
$_wp_deprecated_widgets_callbacks
$wp_actions (array) Keeps a count of the number of times each action has been fired.
$wp_default_secret_key
$pagenow (string)

Browser Detection Booleans

These globals store data about which browser the user is on.

$is_iphone (boolean) iPhone Safari
$is_chrome (boolean) Google Chrome
$is_safari (boolean) Safari
$is_NS4 (boolean) Netscape 4
$is_opera (boolean) Opera
$is_macIE (boolean) Mac Internet Explorer
$is_winIE (boolean) Windows Internet Explorer
$is_gecko (boolean) FireFox
$is_lynx (boolean)
$is_IE (boolean) Internet Explorer

Web Server Detection Booleans

These globals store data about which web server WordPress is running on.

$is_apache (boolean) Apache HTTP Server
$is_IIS (boolean) Microsoft Internet Information Services (IIS)
$is_iis7 (boolean) Microsoft Internet Information Services (IIS) v7.x

$wp_rewrite
$wp_taxonomies
$wp
$l10n
$wp_post_types
$_wp_post_type_features
$wp_post_statuses
$wp_theme_directories
$path
$comment_form_id
$options
$wp_the_query
$wp_query
$wp_widget_factory
$locale
$weekday
$weekday_initial
$weekday_abbrev
$month
$month_abbrev
$wp_locale
$content_width
$_wp_theme_features
$_wp_registered_nav_menus
$_wp_additional_image_sizes
$_wp_default_headers

Logged in User Data

These globals store information about the user logged into the site.

$current_user (object) Returns an object with information about the user. Similar to the object returned by Function_Reference/get_userdata.
$user_login (string) User's username.
$userdata (object) Returns an object with information about the user. Similar to the object returned by Function_Reference/get_userdata.
$user_level (string) User's numerical user level. See User_Levels.
$user_ID (int) Numerical ID of the user.
$user_email (string) User's email address.
$user_url (string) User's website URL.
$user_pass_md5 (string) User's password hashed by MD5.
$user_identity (string) User's nickname.

$pluginDomain
$wpsmiliestrans
$wp_smiliessearch
$wp_admin_bar (object) Global instance of the WP_Admin_Bar class.
$show_admin_bar (boolean) Returns true when the admin bar will be shown.
$wp_styles (object) Global instance of the WP_Styles class. Stores information about registered stylesheets.
$wp_scripts (object) Global instance of the WP_Scripts class. Stores information about registered javascripts.
$wp_header_to_desc (array) A list of all HTTP Status Code Header Descriptions.
$error
$m
$p
$post_parent
$subpost
$subpost_id
$attachment
$attachment_id
$name
$static
$pagename
$page_id
$second (int) 0-59
$minute (int) 0-59
$hour (int) 0-23
$day (int) 1-31
$monthnum (int) 1-12
$year (int) 0-2011
$w (int)
$category_name
$tag
$cat
$tag_id
$author_name
$feed
$tb
$paged (int) The page number used for pagination.
$comments_popup
$meta_key
$meta_value
$preview
$s
$sentence
$fields
$category__in
$category__not_in
$category__and
$post__in
$post__not_in
$tag__in
$tag__not_in
$tag__and
$tag_slug__in
$tag_slug__and
$ignore_sticky_posts
$suppress_filters
$cache_results
$update_post_term_cache
$update_post_meta_cache
$post_type
$posts_per_page
$nopaging
$comments_per_page
$no_found_rows
$order
$query_string (string) Contains the entire query string separated from the URL.
$posts (array) An array of all $post objects, including information on all posts compiled from the global $wp_query.
$post (object) Returns an object with information about the last echoed post, as described in Function_Reference/get_post.
$request (string) The SQL statement used to query for posts.
$template (string) A local directory location of the theme template used.
$wp_did_template_redirect
$comment
$wp_cockneyreplace
$concatenate_scripts
$compress_scripts
$compress_css

Inside the Loop variables

While inside the loop, these globals are set, containing information about the current post being processed.

$id (int) The ID of the content.
$authordata (object) Returns an object with information about the author, set alongside the last $post. Object described in Function_Reference/get_userdata.
$currentday Day of the post.
$currentmonth Month of the post.
$page (int) The page of the post, as specified by the query var page.
$pages (int)The number of pages within a post, which are separated by elements.
$multipage (boolean)Returns true if the post has multiple pages, related to $page and $pages.
$more (boolean) Returns true if there are multiple pages in the post, related to $page and $pages.
$numpages (int) Returns the number of pages in the post, related to $page and $pages.

$wpcommentspopupfile
$wpcommentsjavascript

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