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.
CentOS is a Linux distribution that provides a free, community-supported computing platform functionally compatible with its upstream source, Red Hat Enterprise Linux (RHEL).
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Imperva is a cyber security software and services company for networking, data, and application security.
OpenSSL is a software library for applications that secure communications over computer networks against eavesdropping or need to identify the party at the other end.