[wordpress] Template Hierarchy

Let’s start by an example:

If your blog is at http://example.com/blog/ and a visitor clicks on a link to a category page such as http://example.com/blog/category/your-cat/, WordPress looks for a template file in the current theme’s directory that matches the category’s ID to generate the correct page. More specifically, WordPress follows this procedure:

1. Looks for a template file in the current theme’s directory that matches the category’s slug. If the category slug is “unicorns,” then WordPress looks for a template file named category-unicorns.php.
2. If category-unicorns.php is missing and the category’s ID is 4, WordPress looks for a template file named category-4.php.
3. If category-4.php is missing, WordPress will look for a generic category template file, category.php.
4. If category.php does not exist, WordPress will look for a generic archive template, archive.php.
5. If archive.php is also missing, WordPress will fall back to the main theme template file, index.php.

Visual Overview

The following diagram shows which template files are called to generate a WordPress page based on the WordPress template hierarchy.

Reference:
https://developer.wordpress.org/themes/basics/template-hierarchy/