Child theme: definition

How it works alongside the parent theme

Technically, a child theme is a minimal folder containing at least a style.css file with a header stating Template: followed by the parent theme's folder name, and a functions.php file that loads the parent's stylesheet alongside its own. WordPress then merges the two: any file missing from the child is loaded from the parent, and any file present in the child takes precedence.

On a WooCommerce store, the benefit is immediate: customising a premium theme directly in its original files means those changes are lost the next time you click Update in wp-admin. A child theme isolates these changes in a separate folder, never touched by an update to the parent.

It's also the recommended way to override a WooCommerce template, but the copy path isn't symmetrical: the original file lives in the plugin, under wp-content/plugins/woocommerce/templates/, and has to be copied into wp-content/themes/my-child-theme/woocommerce/. The templates/ segment disappears along the way: templates/single-product/price.php becomes woocommerce/single-product/price.php. A file left inside a templates/ subfolder of the child theme is never loaded by WooCommerce, and the customisation has no effect.