Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
OpenResty is a web platform based on nginx which can run Lua scripts using its LuaJIT engine.
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.