What Is A Theme

In this module, you’ll learn how a theme interacts with WordPress and you will look at the role of CSS within that WordPress theme. You will also explore the definitions of both a framework and a child theme and see how they work.

Prerequisite Skills

  • Basic knowledge of the names of web languages (HTML, CSS, PHP)
  • Ability to edit files with a text editor
  • A desire to learn


  • None needed

Screening Questions

  • Do you want to begin to understand how WordPress sites are built?
  • Do you have basic knowledge of the names of web languages (HTML, CSS, PHP)?
  • Do you have the ability to edit files with a text editor?

Teacher Notes

  • This lesson is meant to be a high-level overview of themes. You will find more details available in other lesson plans.

Hands-on Walkthrough

What is a Theme?

A theme is a collection of files that include HTML, CSS, JavaScript, and PHP code that controls how your site’s information is displayed.

How Does a Theme Interact with WordPress?

Themes are one of the three components that make up a WordPress website. WordPress itself provides the engine and database behind the site. Plugins provide functionality; such as forms and e-commerce. Themes give WordPress websites their look and feel. They are like the skin of your site, or the layer you see on the outside, which is often referred to as the front end of a website.

What is a Theme Framework?

The term “Theme Framework” currently has three meanings:

  • A “drop-in” code library that is used to facilitate development of a theme (e.g., Bootstrap or Foundation)
  • A stand-alone base/starter Theme that is intended either to be forked into another theme (e.g. _s Underscores )
  • A parent theme template (e.g., Genesis)

What these definitions have in common is that they provide code that serves as a base to build upon to create the theme that will actually be used to display the site.

What is a Child Theme?

A child theme is a theme that builds upon another theme, called the parent theme. Child themes allow you to modify, or add to the code of a parent theme. A child theme is the best, safest, and easiest way to modify an existing theme, whether you want to make just one tiny change or completely overhaul it. When you use a child theme, you must also install a parent theme to make it work properly. Child themes are not meant to stand on their own. Instead of modifying the theme files directly, create a child theme, and make your edits there. This will help prevent any updates to the parent theme from breaking your website.


  • None


What must be installed in order to use a child theme?

  1. A starter theme
  2. A framework
  3. A parent theme

Correct Answer: 3. A parent theme

What is the best way to make modifications to an existing theme?

  1. Modify or add code to the parent theme
  2. Create a child theme
  3. Install a new theme

Correct Answer: 2. Create a child theme

Additional Resources

Using Themes