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.
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.
PHP is a general-purpose scripting language used for web development.
Trusted Shops is a company that acts as a 3'rd party representing the common interests of both consumers and retailers.