Basic (main) (category)
| after_setup_theme | Fires on every page load immediately after the theme is initialized. It is normally used to set up basic theme features; see add_theme_support(). |
| init | Fires after WordPress has finished loading but before any HTTP headers are sent. |
| plugins_loaded | Fires immediately after all active plugins have loaded. |
| wp_loaded | Fires after WordPress is fully loaded, when the environment is completely ready to execute code for any request type. |