Creating a WordPress theme from scratch is a task that requires an understanding of programming languages such as HTML, CSS, JavaScript and PHP, but also a familiarity with the structure and specific logic of WordPress. At the heart of this framework are template languages and template tags, which are essential for creating a custom theme. This guide will explore these concepts in detail and provide a solid foundation for anyone looking to develop WordPress themes from scratch.

What is WordPress Template Language?

WordPress's "template language" is not a language in the traditional sense, like PHP or JavaScript. Instead, it refers to the use of WordPress template files and the specific syntax used within those files to interact with WordPress and display dynamic content. These template files are written in PHP and contain HTML mixed with WordPress template tags.

Template Files and the Template Hierarchy

A WordPress theme is made up of several template files, each responsible for a specific part of the website. For example, the header.php file usually contains the website header, while footer.php contains the footer. The index.php file is the default template file that WordPress uses to display content if no other template file is found.

The WordPress template hierarchy defines which template file will be used in different contexts, such as post pages, category pages, archive pages, etc. Knowing this hierarchy is essential to create a theme that behaves as desired in different situations.

Template Tags

Template tags are predefined PHP functions that WordPress uses to fetch and display data from the database. These tags allow developers to display dynamic posts, categories, tags, authors, and other information without needing to write complex SQL queries.

There are different types of template tags, including:

General Tags: Such as get_header() and get_footer(), which include the header and footer parts respectively.
Loop Tags: Such as have_posts() and the_post(), used to iterate over posts or pages.
Post Tags: Such as the_title() and the_content(), which display the title and content of the current post. li>
Comment Tags: Like comments_template(), which includes the comments template.
Navigation Tags: Like paginate_links(), which creates paginated navigation.

Developing a Theme from Scratch

When developing a theme from scratch, you will start by creating the basic file structure. Here are the initial steps:

Create a new folder inside the /wp-content/themes/ directory for your theme.
Create a style.css file with a valid theme header so that WordPress recognizes your theme.
Create a functions.php file, which is where you will add theme-specific functionality and enqueue styles and scripts.
Create the basic template files such as header.php, footer.php, index.php, single.php (for individual posts), and page.php (for pages).
Use template tags to add dynamic content to your template files.

Practical Example: Creating a Basic Loop

One of the most fundamental aspects of a WordPress theme is the loop. The loop is where WordPress processes each post and displays it on the page. Here is an example of how you can use the loop in your index.php file:

<?php if ( have_posts() ) : ?>
    <!-- Start of loop -->
    <?php while ( have_posts() ) : the_post(); ?>
        <h2><?php the_title(); ?></h2>
        <div><?php the_content(); ?></div>
    <?php endwhile; ?>
    <!-- End of loop -->
<?php else : ?>
    <p>Sorry, no posts were found.</p>
<?php endif; ?>

This code checks if there are posts to show and then starts the loop with while ( have_posts() ) : the_post();. Inside the loop, we use template tags like the_title() and the_content() to display the title and content of each post.

Final Considerations

Developing a WordPress theme from scratch is a rewarding process that allows for complete customization and the opportunity to learn more about the inner workings of WordPress. By mastering template language and template tags, you'll have the tools you need to create dynamic, responsive themes that can be adapted to meet any need.

Practice is the key to mastery, so start experimenting with your own themes and don't be afraid to look at the source code of existing themes to understand how experienced developers use WordPress template tags.

Now answer the exercise about the content: