Differences Between Classic, Hybrid, and Full Site Editing (FSE) Themes in WordPress

WordPress, the most popular content management system in the world, has undergone significant changes over the years. One of the most noticeable areas of evolution is in WordPress themes, which dictate the design, layout, and functionality of websites. With the introduction of Full Site Editing (FSE), the way themes are created and used has drastically shifted. Let’s explore the evolution of WordPress themes and understand the differences between Classic, Hybrid, and FSE themes in simple terms.

Evolution of WordPress Themes

When WordPress was first launched in 2003, its primary purpose was blogging. Over the years, it grew into a powerful platform capable of managing all kinds of websites, from personal blogs to large eCommerce stores. Here’s a quick look at the major stages of WordPress theme evolution:

1. Classic Themes (2003–2018)
   • Traditional themes relied heavily on PHP and required knowledge of HTML and CSS for customization.
   • Customization was done through the WordPress Customizer or by editing theme files directly.
   • Functionality was limited to what the theme developer provided, with some customization via widgets and menus.
2. Introduction of the Block Editor (2018)
   • With WordPress 5.0, the Gutenberg block editor was introduced.
   • This editor replaced the old TinyMCE editor and enabled users to build content with blocks.
   • However, classic themes didn’t fully embrace blocks, leading to the next phase.
3. Hybrid Themes (2019–2021)
   • Hybrid themes began integrating block-based features while retaining classic functionalities.
   • They acted as a bridge between Classic themes and the new block-based Full Site Editing (FSE).
4. Full Site Editing Themes (2022–Present)
   • FSE themes revolutionized WordPress by allowing users to design and customize their entire site (not just content) using blocks.
   • No coding skills are required to make significant design changes.

Classic Themes

Classic themes in WordPress are traditional, PHP-based themes that use a predefined structure of files to control a website’s layout, design, and functionality. These themes rely heavily on code and templates, making them less flexible compared to modern block-based themes.

Classic themes separate a website’s content (managed through the WordPress editor) from its presentation (managed by the theme). Developers control the design through PHP, HTML, CSS, and sometimes JavaScript, while users can tweak settings using the Customizer, widgets, or menu options.

How They Work:

Classic themes work by using a hierarchy of template files to control how content is displayed. When a visitor requests a page, WordPress uses its template hierarchy to find the appropriate file, processes the PHP code in it, and sends the final HTML output to the browser.

For instance:

• If someone visits a blog post, WordPress might use the single.php file.
• For a homepage, it might use index.php or front-page.php.
• Developers can create additional templates  category.php or 404.php to handle specific types of pages.

This system gives developers precise control but makes it less accessible for non-technical users.

Customization Level:

• Limited customization for non-developers.
• Heavily dependent on third-party plugins to achieve advanced functionality.

Best For:

• Legacy websites that haven’t transitioned to modern features.
• Developers are comfortable with coding and manual customization.

Hybrid Themes

Hybrid themes are themes that incorporate both classic template-based functionality and block-based features. While they retain classic themes’ underlying structure and workflows, they also support Gutenberg blocks to enhance content creation and editing.

In simple terms, hybrid themes allow you to use the new block editor to create content while still managing the rest of your site—headers, footers, sidebars—through traditional methods like the Customizer or PHP templates.

How They Work:

Hybrid themes combine the old and new. They retain the classic PHP-based architecture but include support for Gutenberg blocks. This means you can use the block editor for creating content but still rely on traditional methods for controlling the site’s layout and structure.

• Content Editing:
  Posts and pages are created using the Gutenberg block editor, allowing users to structure content with drag-and-drop blocks like images, columns, and galleries.
• Site Layouts:
  Headers, footers, and sidebars are controlled using PHP templates or the WordPress Customizer, similar to how classic themes work.
• Advanced Features:
  Developers can extend hybrid themes with block-based templates (template-parts), block areas, or even block-based widgets, gradually incorporating more modern functionality.

Customization Level:

• More flexible than classic themes but not as seamless as FSE themes.
• Limited block-based customization for headers, footers, and templates.

Best For:

• Users transitioning from Classic themes to FSE themes.
• Websites that need a balance between traditional templates and modern blocks.

Full Site Editing (FSE) Themes

FSE (Full Site Editing) themes are WordPress themes that fully embrace the block editor (Gutenberg) for creating and managing all parts of a website. Unlike classic or hybrid themes, which rely on PHP templates and the Customizer for site-wide settings, FSE themes enable users to design and edit everything—from headers and footers to page templates and global styles—directly within the WordPress admin interface.

In essence, FSE themes transform WordPress into a visual website builder, similar to platforms like Wix or Squarespace, but with the flexibility and power of open-source WordPress.

How They Work:

FSE themes embrace the block-first approach. The block editor can design and customize everything on your site—headers, footers, sidebars, and content. This eliminates the need for traditional PHP templates.

FSE themes use a combination of blocks, templates, and styles to provide a seamless website-building experience. Here’s how they operate:

1. Theme JSON File:
   • The theme.json file is the heart of an FSE theme. It defines global settings like fonts, colors, spacing, and block styles.
   • This file gives users control over the design without modifying CSS or PHP.
2. Site Editor:
   • Users can edit templates for their homepage, single posts, category pages, and more directly in the Site Editor.
   • Template parts, like headers and footers, can also be designed and updated visually.
3. Blocks and Patterns:
   • FSE themes use blocks for every design element, from menus and logos to call-to-action sections.
   • Block patterns provide pre-made designs that users can insert and customize.
4. No Customizer or Widgets:
   • Traditional tools like the WordPress Customizer and widgets are replaced by block-based alternatives, ensuring a unified editing experience.

Customization Level:

• Extremely user-friendly, with drag-and-drop functionality.
• Gives complete control over site design without requiring coding.
• Built with the Site Editor, Template Editor, and reusable blocks.

Best For:

• New websites looking for maximum design flexibility.
• Non-technical users who want to create professional-looking websites easily.

Key Differences

Advantages of FSE Themes Over Classic and Hybrid Themes

1. Complete Design Freedom:

• With FSE themes, users can customize every part of their website without relying on a developer or third-party tools.

2. User-Friendly:

• The visual editing interface is intuitive, making it easy for beginners to design professional websites.

3. Consistency Across the Site:

• Global Styles ensures that typography, colors, and other design elements are uniform throughout the website.

4. No Coding Required:

• Advanced features like template editing and global styling can be achieved without writing a single line of code.

5. Future-Proof:

• FSE themes are built to align with WordPress’s long-term vision of being a fully block-based platform, ensuring compatibility with future updates.

6. Reduced Plugin Dependence:

• Features like headers, footers, and reusable blocks are built into FSE themes, reducing the need for additional plugins.

Conclusion

The journey of WordPress themes reflects the platform’s growth from a simple blogging tool to a robust website builder. While Classic themes and Hybrid themes served their purpose during their time, FSE themes are paving the way for a more user-friendly and flexible future.

If you’re building a new website or looking to revamp an existing one, FSE themes are a great choice. They empower users with design control, simplify the editing process, and ensure compatibility with WordPress’s ongoing evolution.

At AcmeThemes, we embrace these changes and continue to provide themes that cater to both traditionalists and modern creators. Explore our collection of themes and find the perfect fit for your website!

I hope you enjoyed reading this article!

Please check out our other recent article:

• Best Free Full Site Editing (FSE) WordPress Themes