Perhaps the greatest benefit of using WordPress to run your website is the ease with which you can change the look of the site.
Pick a new theme, and presto! A whole new look.
Or dig into the style.css to adjust the colors of your links or change the headline style to a more pleasing font.
Anything is possible. You can even (with a little knowledge and a bit of bravery) go to work on the php files to change the layout or functionality of your website.
But tweaking your theme presents a problem. What if the original developer issues a new release? One click of the update button on a theme you’ve customized, and all your changes will be lost.
The solution? Use a child theme instead.
How Child Themes Work
Simply put, a child theme is a special kind of template that contains only those files that have been edited. For everything else, it calls on the parent theme for help.
For example, Genesis by Studio Press is a “parent theme.” It contains all the functions, page templates, jquery code, and everything else that makes a theme run. Child themes such as Lifestyle Pro or Executive (what this site is using as of the time of this writing) include additional files to further customize the Genesis framework.
Genesis is updated frequently to help keep up with WordPress updates and security holes, but the child themes never are. You can edit the child themes as much as you like, and you’ll never lose your changes.
One thing to keep in mind, though: You must keep both the parent theme and the child theme installed on your site, even though the child is the only one that’s activated. No child theme will work without its parent.
Creating Your Own Child Themes
You can create a child theme from nearly any other theme. For example, you could start with one of WordPress’ default themes, Twenty-twelve or Twenty-thirteen, and add a child theme simply by creating a folder in your themes directory and adding a style sheet. That’s the only file that is required, though you can certainly (and most likely will) add more files for greater customization.
WordPress has a good primer on creating a child theme here.
No Child Theme Required
Some themes allow full customization without the use of a child theme, and without the risk of losing your changes when you update. These themes often contain “options pages” within the dashboard where you can change colors and fonts and make other customizations at the click of a button. They also often contain files called custom.css in which you can do even more fine tuning.
Before you begin making changes to your WordPress site, be sure you know what kind of theme you’re using, and if it requires (or is) a child theme. You’ll save yourself some potential headaches later by making your customizations the right way, whether that’s with a child theme or by using your theme’s built-in options page.