Unless otherwise indicated, the code snippets you see below should be placed into your theme’s functions.php file.

Here is the code to enable HTML5 markup on your site:

// Adds HTML5 markup structure.
add_theme_support(
	'html5', array(
		'caption',
		'comment-form',
		'comment-list',
		'gallery',
		'search-form',
	)
);

Note: The previous method for enabling HTML5 markup was somewhat different. Although the old code won’t cause issues with your site, an error message may appear if Debug mode is active.

It is advisable for users to update their functions.php files or obtain a new version of the theme since all theme downloads now include the updated code.