What is Child Theme: A Basic Understanding for the Curious

by mmhossain · Published June 21, 2019 · Updated December 10, 2020

We’re going to highlight the Child Theme fact in the WordPress background. Where there is child there is parent. So a Child Theme is the theme that inherits the look and feel of its Parent Theme and all its functionality and features. Child Theme is created to modify a theme without affecting the Parent Theme.

Technically, Child Theme overrides the functionality of the Parent Theme as much as Child Theme is modified.

Now question; what is Parent Theme and where does it exist in WordPress?

An overview of Parent theme

The main theme that we use to structure WordPress’ look and appearance is Parent Theme; such as Twenty Seventy Theme. It is complete theme that includes all of the resources and WordPress template files essential for a theme to work. Without a Theme WordPress cannot run. Hence, WordPress being installed, we get a built-in default theme such as Twenty Nineteen (latest) or so which we can change later. This is Parent Theme.

Basic understanding of Child Theme focus

Noted, a Theme shapes the WordPress with visible interfaces like Header, Footer, Menu, Sidebar, Post, Page etc. We can change and add these visible structures any time we need by modifying CSS and PHP files that comprises the theme infrastructure.

Suppose you want to change the font-size and font-family of your Post. For this you have to change the values of these two properties located in the relevant field of CSS file of your Theme.

Noted, there is also visual CSS editor plugin like Yellow Pencil to edit WordPress site. But this process is completely dependent on a plugin and it cannot cover up all-out customization of a Theme.

Why Child Theme enters the scenario

Customizing a WordPress Parent Theme is not so easy. It is especially true for the non-techy WordPressers. There are many reasons why all- beginners to advanced– should avoid customizing process in WordPress Parent theme itself. Rather it is wise to create a Child Theme and customize it to modify your WordPress site without leaving any impact on the Main or Parent theme.

Here are the obvious reasons for not customizing Parent Theme but create a Child Theme and apply Customization on it instead-

Customizing a theme is difficult job. A little mistake of modification can disfigure the site which may lead to great hassle.
When Parent Theme is updated, all customization disappears. So the webmaster encounters a great loss of hard labor and time.
Modification in Child Theme is portable, can easily be copied and stored separately for future use.
Child Theme ensures safest and most convenient customization. Modification in Child Theme is applied instantly after Parent Theme gets updated. No attempt required.
It is a great scope to learn and experience theme development.

However, in the earlier days of WordPress development, there was no way to build-up an own customization process by using such a Child Theme. The few changes which only the developers could imagine to make, were always in threat of getting lost if themes were updated and on the risk of getting hacked if themes were not updated.

To solve this crucial problem, WordPress core developers came forward and introduced the concept of Parent Theme and Child Theme.

Thus Child Theme came into being that paved the way to customizing any WordPress theme simple way without risking customized coding and site’s security even by average WordPress developers and owners.
Now doesn’t this question peeps up in mind- How to create a Child Theme in WordPress. Yes! We already arranged that tutorial for you in another lesson. Just follow this link-