Apache is a free and open-source cross-platform web server software.
Authorize.net is a secure online payment gateway service that enables businesses to accept payments through various channels, such as ecommerce websites, mobile devices, and retail stores, providing a trusted platform for processing credit card and electronic cheque payments.
Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
PHP is a general-purpose scripting language used for web development.
Ubuntu is a free and open-source operating system on Linux for the enterprise server, desktop, cloud, and IoT.
Varnish is a reverse caching proxy.