Liquid

Liquid was created by Shopify and is the language themes are written in. Using objects (e.g. product, collection, cart), tags for logic (if, for) and filters for output (e.g. money, img_url), Liquid renders dynamic store data into static HTML that is delivered to the browser.

Liquid becomes relevant for merchants the moment the theme needs customizing: custom sections, individual product presentations, metafield output or logic like 'show a volume-pricing hint above quantity X'. Liquid customizations are the standard route to individualization — far cheaper and more maintainable than a headless architecture.

Important to know: Liquid is rendered server-side by Shopify and deliberately constrained — there is no database access and no arbitrary programming. Dynamic behavior in the browser is added with JavaScript; external data comes in through the Storefront or Admin API.