Apache is a free and open-source cross-platform web server software.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
Ubuntu is a free and open-source operating system on Linux for the enterprise server, desktop, cloud, and IoT.
W3.CSS is a CSS framework developed by the World Wide Web Consortium (W3C), the main international standards organisation for the World Wide Web.