WordPress at a glance
action is not described

init action-hook . WP 1.5.0

Fires after WordPress has finished loading but before any headers are sent.

Most of WP is loaded at this stage, and the user is authenticated. WP continues to load on the 'init' hook that follows (e.g. widgets), and many plugins instantiate themselves on it for all sorts of reasons (e.g. they need a user, a taxonomy, etc.).

If you wish to plug an action once WP is loaded, use the 'wp_loaded' hook below.

Usage

add_action( 'init', 'action_function_name_3397' );
function action_function_name_3397(){
	// action...
}

Changelog

Since 1.5.0 Introduced.

Where the hook is called

In file: /wp-settings.php
init
wp-settings.php 546
do_action( 'init' );

Where in WP core the hook is used WordPress

wp-settings.php 126
add_action( 'init', 'register_block_core_archives' );
wp-settings.php 43
add_action( 'init', 'register_block_core_block' );
wp-settings.php 63
add_action( 'init', 'register_block_core_calendar' );
wp-settings.php 99
add_action( 'init', 'register_block_core_categories' );
wp-settings.php 67
add_action( 'init', 'register_core_block_types_from_metadata' );
wp-settings.php 163
add_action( 'init', 'register_block_core_latest_comments' );
wp-settings.php 190
add_action( 'init', 'register_block_core_latest_posts' );
wp-settings.php 113
add_action( 'init', 'register_block_core_rss' );
wp-settings.php 89
add_action( 'init', 'register_block_core_search' );
wp-settings.php 31
add_action( 'init', 'register_block_core_shortcode' );
wp-settings.php 41
add_action( 'init', 'register_block_core_social_link' );
wp-settings.php 61
add_action( 'init', 'register_block_core_tag_cloud' );
wp-settings.php 370
remove_action( 'init', 'wp_cron' );
wp-settings.php 143
add_action( 'init', array( $this, 'init' ), 0 );
wp-settings.php 545
add_action( 'init', 'wp_widgets_init', 1 );
wp-settings.php 454
add_action( 'init', 'rest_api_init' );
wp-settings.php 525
add_action( 'init', 'create_initial_taxonomies', 0 ); // Highest priority.
wp-settings.php 500
add_action( 'init', 'kses_init' );
wp-settings.php 486
add_action( 'init', 'create_initial_post_types', 0 ); // Highest priority.
wp-settings.php 461
add_action( 'init', 'wp_sitemaps_get_server' );
wp-settings.php 304
add_action( 'init', '_register_core_block_patterns_and_categories' );
wp-settings.php 402
add_action( 'init', '_show_post_preview' );
wp-settings.php 372
add_action( 'init', 'wp_schedule_delete_old_privacy_export_files' );
wp-settings.php 352
add_action( 'init', 'smilies_init', 5 );
wp-settings.php 334
add_action( 'init', 'wp_cron' );
wp-settings.php 305
add_action( 'init', 'check_theme_switched', 99 );
wp-settings.php 131
add_action( 'init', 'wp_init_targeted_link_rel_filters' );
wp-settings.php 16
add_action( 'init', 'ms_subdomain_constants' );
wp-settings.php 25
add_action( 'init', 'maybe_add_existing_user_to_blog' );
wp-settings.php 896
add_action( 'init', 'wp_schedule_update_checks' );