Shopify is a cloud-based, ecommerce platform used to create online stores and sell products. It provides users with an intuitive interface that allows them to easily set up their store, manage inventory, accept payments, and ship orders. It also provides powerful tools for customizing the look and feel of the store, as well as marketing, analytics, and customer service features. Shopify is popular among JavaScript developers because it offers a wide range of APIs and SDKs which allow them to extend the functionality of the platform.