Apache is a free and open-source cross-platform web server software.
Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
Drupal is a free and open-source web content management framework.
Stripe offers online payment processing for internet businesses as well as fraud prevention, invoicing and subscription management.