Hooks allow you to add extra content or custom code at various areas inside the Starter Blog theme. For example, you might want some advertisement below all of your blog posts. Hooks make such dynamic things easily.

How to Use Hooks

function your_function_name() { ?>
	Insert your custom content here
<?php
}
add_action( 'hook_name', 'your_function_name' );

In the example above, replace hook_name with the hook where you want to add something.

Learn more: https://developer.wordpress.org/plugins/hooks/