diff --git a/wp-admin/admin-ajax.php b/wp-admin/admin-ajax.php
index 07f3394a4e..a52de826ed 100644
--- a/wp-admin/admin-ajax.php
+++ b/wp-admin/admin-ajax.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * WordPress AJAX Process Execution.
+ * WordPress Ajax Process Execution
  *
  * @package WordPress
  * @subpackage Administration
@@ -9,7 +9,7 @@
  */
 
 /**
- * Executing AJAX process.
+ * Executing Ajax process.
  *
  * @since 2.1.0
  */
@@ -81,20 +81,20 @@ add_action( 'wp_ajax_nopriv_heartbeat', 'wp_ajax_nopriv_heartbeat', 1 );
 
 if ( is_user_logged_in() ) {
 	/**
-	 * Fires authenticated AJAX actions for logged-in users.
+	 * Fires authenticated Ajax actions for logged-in users.
 	 *
 	 * The dynamic portion of the hook name, `$_REQUEST['action']`,
-	 * refers to the name of the AJAX action callback being fired.
+	 * refers to the name of the Ajax action callback being fired.
 	 *
 	 * @since 2.1.0
 	 */
 	do_action( 'wp_ajax_' . $_REQUEST['action'] );
 } else {
 	/**
-	 * Fires non-authenticated AJAX actions for logged-out users.
+	 * Fires non-authenticated Ajax actions for logged-out users.
 	 *
 	 * The dynamic portion of the hook name, `$_REQUEST['action']`,
-	 * refers to the name of the AJAX action callback being fired.
+	 * refers to the name of the Ajax action callback being fired.
 	 *
 	 * @since 2.8.0
 	 */
diff --git a/wp-admin/custom-background.php b/wp-admin/custom-background.php
index dba32c661e..a03986f594 100644
--- a/wp-admin/custom-background.php
+++ b/wp-admin/custom-background.php
@@ -410,7 +410,7 @@ if ( current_theme_supports( 'custom-background', 'default-color' ) )
 	}
 
 	/**
-	 * AJAX handler for adding custom background context to an attachment.
+	 * Ajax handler for adding custom background context to an attachment.
 	 *
 	 * Triggered when the user adds a new background image from the
 	 * Media Manager.
diff --git a/wp-admin/includes/ajax-actions.php b/wp-admin/includes/ajax-actions.php
index e986785c9e..c16f338cdb 100644
--- a/wp-admin/includes/ajax-actions.php
+++ b/wp-admin/includes/ajax-actions.php
@@ -32,7 +32,7 @@ function wp_ajax_nopriv_heartbeat() {
 		$data = wp_unslash( (array) $_POST['data'] );
 
 		/**
-		 * Filters Heartbeat AJAX response in no-privilege environments.
+		 * Filters Heartbeat Ajax response in no-privilege environments.
 		 *
 		 * @since 3.6.0
 		 *
@@ -44,7 +44,7 @@ function wp_ajax_nopriv_heartbeat() {
 	}
 
 	/**
-	 * Filters Heartbeat AJAX response when no data is passed.
+	 * Filters Heartbeat Ajax response when no data is passed.
 	 *
 	 * @since 3.6.0
 	 *
@@ -132,7 +132,7 @@ function wp_ajax_ajax_tag_search() {
 	$s = trim( $s );
 
 	/**
-	 * Filters the minimum number of characters required to fire a tag search via AJAX.
+	 * Filters the minimum number of characters required to fire a tag search via Ajax.
 	 *
 	 * @since 4.0.0
 	 *
@@ -335,7 +335,7 @@ function wp_ajax_logged_in() {
 /**
  * Sends back current comment total and new page links if they need to be updated.
  *
- * Contrary to normal success AJAX response ("1"), die with time() on success.
+ * Contrary to normal success Ajax response ("1"), die with time() on success.
  *
  * @access private
  * @since 2.7.0
@@ -2164,7 +2164,7 @@ function wp_ajax_set_post_thumbnail() {
 }
 
 /**
- * AJAX handler for setting the featured image for an attachment.
+ * Ajax handler for setting the featured image for an attachment.
  *
  * @since 4.0.0
  *
@@ -2391,7 +2391,7 @@ function wp_ajax_query_attachments() {
 		$query['post_status'] .= ',private';
 
 	/**
-	 * Filters the arguments passed to WP_Query during an AJAX
+	 * Filters the arguments passed to WP_Query during an Ajax
 	 * call for querying attachments.
 	 *
 	 * @since 3.7.0
@@ -2908,7 +2908,7 @@ function wp_ajax_query_themes() {
 }
 
 /**
- * Apply [embed] AJAX handlers to a string.
+ * Apply [embed] Ajax handlers to a string.
  *
  * @since 4.0.0
  *
@@ -3069,7 +3069,7 @@ function wp_ajax_parse_media_shortcode() {
 }
 
 /**
- * AJAX handler for destroying multiple open sessions for a user.
+ * Ajax handler for destroying multiple open sessions for a user.
  *
  * @since 4.1.0
  */
@@ -3104,7 +3104,7 @@ function wp_ajax_destroy_sessions() {
 }
 
 /**
- * AJAX handler for saving a post from Press This.
+ * Ajax handler for saving a post from Press This.
  *
  * @since 4.2.0
  *
@@ -3119,7 +3119,7 @@ function wp_ajax_press_this_save_post() {
 }
 
 /**
- * AJAX handler for creating new category from Press This.
+ * Ajax handler for creating new category from Press This.
  *
  * @since 4.2.0
  *
@@ -3134,7 +3134,7 @@ function wp_ajax_press_this_add_category() {
 }
 
 /**
- * AJAX handler for cropping an image.
+ * Ajax handler for cropping an image.
  *
  * @since 4.3.0
  *
@@ -3278,7 +3278,7 @@ function wp_ajax_save_wporg_username() {
 }
 
 /**
- * AJAX handler for installing a theme.
+ * Ajax handler for installing a theme.
  *
  * @since 4.6.0
  *
@@ -3374,7 +3374,7 @@ function wp_ajax_install_theme() {
 }
 
 /**
- * AJAX handler for updating a theme.
+ * Ajax handler for updating a theme.
  *
  * @since 4.6.0
  *
@@ -3455,7 +3455,7 @@ function wp_ajax_update_theme() {
 }
 
 /**
- * AJAX handler for deleting a theme.
+ * Ajax handler for deleting a theme.
  *
  * @since 4.6.0
  *
@@ -3522,7 +3522,7 @@ function wp_ajax_delete_theme() {
 }
 
 /**
- * AJAX handler for installing a plugin.
+ * Ajax handler for installing a plugin.
  *
  * @since 4.6.0
  *
@@ -3608,7 +3608,7 @@ function wp_ajax_install_plugin() {
 }
 
 /**
- * AJAX handler for updating a plugin.
+ * Ajax handler for updating a plugin.
  *
  * @since 4.2.0
  *
@@ -3710,7 +3710,7 @@ function wp_ajax_update_plugin() {
 }
 
 /**
- * AJAX handler for deleting a plugin.
+ * Ajax handler for deleting a plugin.
  *
  * @since 4.6.0
  *
@@ -3775,7 +3775,7 @@ function wp_ajax_delete_plugin() {
 }
 
 /**
- * AJAX handler for searching plugins.
+ * Ajax handler for searching plugins.
  *
  * @since 4.6.0
  *
@@ -3816,7 +3816,7 @@ function wp_ajax_search_plugins() {
 }
 
 /**
- * AJAX handler for searching plugins to install.
+ * Ajax handler for searching plugins to install.
  *
  * @since 4.6.0
  *
@@ -3854,7 +3854,7 @@ function wp_ajax_search_install_plugins() {
 }
 
 /**
- * AJAX handler for testing if a URL exists.
+ * Ajax handler for testing if a URL exists.
  *
  * Used in the editor.
  *
diff --git a/wp-admin/includes/class-wp-list-table.php b/wp-admin/includes/class-wp-list-table.php
index 0347919988..c15cdfe207 100644
--- a/wp-admin/includes/class-wp-list-table.php
+++ b/wp-admin/includes/class-wp-list-table.php
@@ -123,10 +123,10 @@ class WP_List_Table {
 	 *                            in the list table, e.g. 'posts'. Default empty.
 	 *     @type string $singular Singular label for an object being listed, e.g. 'post'.
 	 *                            Default empty
-	 *     @type bool   $ajax     Whether the list table supports AJAX. This includes loading
+	 *     @type bool   $ajax     Whether the list table supports Ajax. This includes loading
 	 *                            and sorting data, for example. If true, the class will call
 	 *                            the _js_vars() method in the footer to provide variables
-	 *                            to any scripts handling AJAX events. Default false.
+	 *                            to any scripts handling Ajax events. Default false.
 	 *     @type string $screen   String containing the hook name used to determine the current
 	 *                            screen. If left null, the current screen will be automatically set.
 	 *                            Default null.
diff --git a/wp-admin/includes/class-wp-press-this.php b/wp-admin/includes/class-wp-press-this.php
index 4d6b671c35..a00bbaa40e 100644
--- a/wp-admin/includes/class-wp-press-this.php
+++ b/wp-admin/includes/class-wp-press-this.php
@@ -96,7 +96,7 @@ class WP_Press_This {
 	}
 
 	/**
-	 * AJAX handler for saving the post as draft or published.
+	 * Ajax handler for saving the post as draft or published.
 	 *
 	 * @since 4.2.0
 	 * @access public
@@ -189,7 +189,7 @@ class WP_Press_This {
 	}
 
 	/**
-	 * AJAX handler for adding a new category.
+	 * Ajax handler for adding a new category.
 	 *
 	 * @since 4.2.0
 	 * @access public
diff --git a/wp-admin/includes/class-wp-themes-list-table.php b/wp-admin/includes/class-wp-themes-list-table.php
index c3ca425d0d..a232cd05b2 100644
--- a/wp-admin/includes/class-wp-themes-list-table.php
+++ b/wp-admin/includes/class-wp-themes-list-table.php
@@ -42,7 +42,7 @@ class WP_Themes_List_Table extends WP_List_Table {
 	 * @return bool
 	 */
 	public function ajax_user_can() {
-		// Do not check edit_theme_options here. AJAX calls for available themes require switch_themes.
+		// Do not check edit_theme_options here. Ajax calls for available themes require switch_themes.
 		return current_user_can( 'switch_themes' );
 	}
 
diff --git a/wp-admin/includes/dashboard.php b/wp-admin/includes/dashboard.php
index ae40a94636..e517f956c7 100644
--- a/wp-admin/includes/dashboard.php
+++ b/wp-admin/includes/dashboard.php
@@ -955,7 +955,7 @@ function wp_dashboard_rss_output( $widget_id ) {
  * If $check_urls is empty, look for the rss feed url found in the dashboard
  * widget options of $widget_id. If cached, call $callback, a function that
  * echoes out output for this widget. If not cache, echo a "Loading..." stub
- * which is later replaced by AJAX call (see top of /wp-admin/index.php)
+ * which is later replaced by Ajax call (see top of /wp-admin/index.php)
  *
  * @since 2.5.0
  *
diff --git a/wp-admin/includes/template.php b/wp-admin/includes/template.php
index 7cd466144d..0de80e764d 100644
--- a/wp-admin/includes/template.php
+++ b/wp-admin/includes/template.php
@@ -203,7 +203,7 @@ function wp_popular_terms_checklist( $taxonomy, $default = 0, $number = 10, $ech
 	$popular_ids = array();
 	foreach ( (array) $terms as $term ) {
 		$popular_ids[] = $term->term_id;
-		if ( !$echo ) // hack for AJAX use
+		if ( !$echo ) // Hack for Ajax use.
 			continue;
 		$id = "popular-$taxonomy-$term->term_id";
 		$checked = in_array( $term->term_id, $checked_terms ) ? 'checked="checked"' : '';
diff --git a/wp-admin/link.php b/wp-admin/link.php
index 802745fc2c..bcfe578fb0 100644
--- a/wp-admin/link.php
+++ b/wp-admin/link.php
@@ -3,7 +3,7 @@
  * Manage link administration actions.
  *
  * This page is accessed by the link management pages and handles the forms and
- * AJAX processes for link actions.
+ * Ajax processes for link actions.
  *
  * @package WordPress
  * @subpackage Administration
diff --git a/wp-includes/class-wp-ajax-response.php b/wp-includes/class-wp-ajax-response.php
index 4c18569f4a..f02d24ee75 100644
--- a/wp-includes/class-wp-ajax-response.php
+++ b/wp-includes/class-wp-ajax-response.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * Send XML response back to AJAX request.
+ * Send XML response back to Ajax request.
  *
  * @package WordPress
  * @since 2.1.0
diff --git a/wp-includes/class-wp-customize-manager.php b/wp-includes/class-wp-customize-manager.php
index 2c808bb666..e277a12cc6 100644
--- a/wp-includes/class-wp-customize-manager.php
+++ b/wp-includes/class-wp-customize-manager.php
@@ -305,14 +305,14 @@ final class WP_Customize_Manager {
 	}
 
 	/**
-	 * Return true if it's an AJAX request.
+	 * Return true if it's an Ajax request.
 	 *
 	 * @since 3.4.0
 	 * @since 4.2.0 Added `$action` param.
 	 * @access public
 	 *
-	 * @param string|null $action Whether the supplied AJAX action is being run.
-	 * @return bool True if it's an AJAX request, false otherwise.
+	 * @param string|null $action Whether the supplied Ajax action is being run.
+	 * @return bool True if it's an Ajax request, false otherwise.
 	 */
 	public function doing_ajax( $action = null ) {
 		$doing_ajax = ( defined( 'DOING_AJAX' ) && DOING_AJAX );
@@ -333,11 +333,11 @@ final class WP_Customize_Manager {
 
 	/**
 	 * Custom wp_die wrapper. Returns either the standard message for UI
-	 * or the AJAX message.
+	 * or the Ajax message.
 	 *
 	 * @since 3.4.0
 	 *
-	 * @param mixed $ajax_message AJAX return
+	 * @param mixed $ajax_message Ajax return
 	 * @param mixed $message UI message
 	 */
 	protected function wp_die( $ajax_message, $message = null ) {
@@ -353,7 +353,7 @@ final class WP_Customize_Manager {
 	}
 
 	/**
-	 * Return the AJAX wp_die() handler if it's a customized request.
+	 * Return the Ajax wp_die() handler if it's a customized request.
 	 *
 	 * @since 3.4.0
 	 *
@@ -609,7 +609,7 @@ final class WP_Customize_Manager {
 	}
 
 	/**
-	 * Prevents AJAX requests from following redirects when previewing a theme
+	 * Prevents Ajax requests from following redirects when previewing a theme
 	 * by issuing a 200 response instead of a 30x.
 	 *
 	 * Instead, the JS will sniff out the location header.
@@ -762,7 +762,7 @@ final class WP_Customize_Manager {
 
 	/**
 	 * Prevent sending a 404 status when returning the response for the customize
-	 * preview, since it causes the jQuery AJAX to fail. Send 200 instead.
+	 * preview, since it causes the jQuery Ajax to fail. Send 200 instead.
 	 *
 	 * @since 4.0.0
 	 * @access public
@@ -1142,7 +1142,7 @@ final class WP_Customize_Manager {
 		);
 
 		/**
-		 * Filters response data for a successful customize_save AJAX request.
+		 * Filters response data for a successful customize_save Ajax request.
 		 *
 		 * This filter does not apply if there was a nonce or authentication failure.
 		 *
diff --git a/wp-includes/class-wp-embed.php b/wp-includes/class-wp-embed.php
index 888dcd33da..17a976f2e6 100644
--- a/wp-includes/class-wp-embed.php
+++ b/wp-includes/class-wp-embed.php
@@ -38,7 +38,7 @@ class WP_Embed {
 		// Attempts to embed all URLs in a post
 		add_filter( 'the_content', array( $this, 'autoembed' ), 8 );
 
-		// After a post is saved, cache oEmbed items via AJAX
+		// After a post is saved, cache oEmbed items via Ajax
 		add_action( 'edit_form_advanced', array( $this, 'maybe_run_ajax_cache' ) );
 		add_action( 'edit_page_form', array( $this, 'maybe_run_ajax_cache' ) );
 	}
@@ -75,7 +75,7 @@ class WP_Embed {
 
 	/**
 	 * If a post/page was saved, then output JavaScript to make
-	 * an AJAX request that will call WP_Embed::cache_oembed().
+	 * an Ajax request that will call WP_Embed::cache_oembed().
 	 */
 	public function maybe_run_ajax_cache() {
 		$post = get_post();
diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 3159e8c460..ee92179352 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -2569,7 +2569,7 @@ function wp_die( $message = '', $title = '', $args = array() ) {
 
 	if ( defined( 'DOING_AJAX' ) && DOING_AJAX ) {
 		/**
-		 * Filters callback for killing WordPress execution for AJAX requests.
+		 * Filters the callback for killing WordPress execution for Ajax requests.
 		 *
 		 * @since 3.4.0
 		 *
@@ -2578,7 +2578,7 @@ function wp_die( $message = '', $title = '', $args = array() ) {
 		$function = apply_filters( 'wp_die_ajax_handler', '_ajax_wp_die_handler' );
 	} elseif ( defined( 'XMLRPC_REQUEST' ) && XMLRPC_REQUEST ) {
 		/**
-		 * Filters callback for killing WordPress execution for XML-RPC requests.
+		 * Filters the callback for killing WordPress execution for XML-RPC requests.
 		 *
 		 * @since 3.4.0
 		 *
@@ -2587,7 +2587,7 @@ function wp_die( $message = '', $title = '', $args = array() ) {
 		$function = apply_filters( 'wp_die_xmlrpc_handler', '_xmlrpc_wp_die_handler' );
 	} else {
 		/**
-		 * Filters callback for killing WordPress execution for all non-AJAX, non-XML-RPC requests.
+		 * Filters the callback for killing WordPress execution for all non-Ajax, non-XML-RPC requests.
 		 *
 		 * @since 3.0.0
 		 *
diff --git a/wp-includes/pluggable.php b/wp-includes/pluggable.php
index 37a749bd1f..a9d350489b 100644
--- a/wp-includes/pluggable.php
+++ b/wp-includes/pluggable.php
@@ -610,7 +610,7 @@ function wp_validate_auth_cookie($cookie = '', $scheme = '') {
 	$token = $cookie_elements['token'];
 	$expired = $expiration = $cookie_elements['expiration'];
 
-	// Allow a grace period for POST and AJAX requests
+	// Allow a grace period for POST and Ajax requests
 	if ( defined('DOING_AJAX') || 'POST' == $_SERVER['REQUEST_METHOD'] ) {
 		$expired += HOUR_IN_SECONDS;
 	}
@@ -667,7 +667,7 @@ function wp_validate_auth_cookie($cookie = '', $scheme = '') {
 		return false;
 	}
 
-	// AJAX/POST grace period set above
+	// Ajax/POST grace period set above
 	if ( $expiration < time() ) {
 		$GLOBALS['login_grace_period'] = 1;
 	}
@@ -1075,7 +1075,7 @@ endif;
 
 if ( !function_exists('check_ajax_referer') ) :
 /**
- * Verifies the AJAX request to prevent processing requests external of the blog.
+ * Verifies the Ajax request to prevent processing requests external of the blog.
  *
  * @since 2.0.3
  *
@@ -1101,11 +1101,11 @@ function check_ajax_referer( $action = -1, $query_arg = false, $die = true ) {
 	$result = wp_verify_nonce( $nonce, $action );
 
 	/**
-	 * Fires once the AJAX request has been validated or not.
+	 * Fires once the Ajax request has been validated or not.
 	 *
 	 * @since 2.1.0
 	 *
-	 * @param string    $action The AJAX nonce action.
+	 * @param string    $action The Ajax nonce action.
 	 * @param false|int $result False if the nonce is invalid, 1 if the nonce is valid and generated between
 	 *                          0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
 	 */
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 8c1f48bf40..04c3f282c9 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.6-beta2-38027';
+$wp_version = '4.6-beta2-38028';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.
diff --git a/wp-settings.php b/wp-settings.php
index 3189718e8e..37a31c2fe7 100644
--- a/wp-settings.php
+++ b/wp-settings.php
@@ -424,7 +424,7 @@ if ( is_multisite() ) {
 /**
  * This hook is fired once WP, all plugins, and the theme are fully loaded and instantiated.
  *
- * AJAX requests should use wp-admin/admin-ajax.php. admin-ajax.php can handle requests for
+ * Ajax requests should use wp-admin/admin-ajax.php. admin-ajax.php can handle requests for
  * users not logged in.
  *
  * @link https://codex.wordpress.org/AJAX_in_Plugins