display_header() WordPress Function

function display_header( $body_classes = '' ) {
	header( 'Content-Type: text/html; charset=utf-8' );
	if ( is_rtl() ) {
		$body_classes .= 'rtl';
	}
	if ( $body_classes ) {
		$body_classes = ' ' . $body_classes;
	}
	?>
<!DOCTYPE html>
<html <?php language_attributes(); ?>>
<head>
	<meta name="viewport" content="width=device-width" />
	<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
	<meta name="robots" content="noindex,nofollow" />
	<title><?php _e( 'WordPress &rsaquo; Installation' ); ?></title>
	<?php wp_admin_css( 'install', true ); ?>
</head>
<body class="wp-core-ui<?php echo $body_classes; ?>">
<p id="logo"><?php _e( 'WordPress' ); ?></p>

	<?php
} // End display_header().
Uses	Description
wp-includes/l10n.php:_e()	Display translated text.
wp-includes/general-template.php:language_attributes()	Displays the language attributes for the ‘html’ tag.
wp-includes/general-template.php:wp_admin_css()	Enqueues or directly prints a stylesheet link to the specified CSS file.
wp-includes/l10n.php:is_rtl()	Determines whether the current locale is right-to-left (RTL).