There are hundreds of hooks available in WordPress—way too many to cover in this book. You can learn more about them by going online. Start out at these online reference sites:
- The Plugin API article contains very thorough information about writing plugins and using hooks, at: https://codex.wordpress.org/Plugin_API.
- For a complete list of action hooks, visit https://codex.wordpress.org/Plugin_API/Action_Reference.
- For a complete list of filter hooks, visit https://codex.wordpress.org/Plugin_API/Filter_Reference.
- You may also want to take a step back and look at the general Plugin Resources page in the WordPress Codex at https://codex.wordpress.org/Plugin_Resources.
- Another page that you might find very helpful is the new Code Reference for developers: https://developer.wordpress.org/reference/.
- A key resource to bookmark if you want to build plugins for the new block-based editor is the Gutenberg Handbook, available at https://wordpress.org/gutenberg/handbook/.
- If you want to submit your plugin to the WordPress plugin repository, you'll need to take steps similar to those that you took when preparing a theme, and you'll also need to get hooked up to the WordPress SVN repository. Learn more about how to submit a plugin to the WordPress plugin repository at https://developer.wordpress.org/plugins/wordpress-org/.