Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PHP is a general-purpose scripting language used for web development.
Pure CSS is a set of small, responsive CSS modules that can be used in web projects.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
StackPath is a cloud computing and services provider.