What is the primary function of a JSON file in a Shopify theme?

The primary function of a JSON file in a Shopify theme is to store configuration settings. JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write and easy for machines to parse and generate. In the context of Shopify themes, JSON files are commonly used for theme settings and configurations. For instance, the settings_data.json file contains user-defined settings for the theme's configuration, such as colors, typography choices, and layout preferences. This allows for an organized way to manage various configurations that directly impact the appearance and behavior of the store, enabling merchants to customize their online presence without delving into the theme's code.

In contrast, the other choices refer to different functionalities within a Shopify theme. Stylesheets are defined using CSS files, which control the visual presentation of a store. Product listings are typically created using Liquid templates and not directly through JSON files. Template code is also held within Liquid files, which provide the structure and logic for how different types of content are rendered on the site. Thus, while those other options are essential components of a Shopify theme, they do not pertain to the specific role of JSON files in managing configuration settings.