Amazon Pay is an online payments processing service that is owned by Amazon. It lets you use the payment methods associated with your Amazon account to make payments for goods and services.
Apache is a free and open-source cross-platform web server software.
Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
Modernizr is a JavaScript library that detects the features available in a user's browser.
Shopware is an enterprise-level ecommerce platform.
A modest JavaScript framework for the HTML you already have.