Apache is a free and open-source cross-platform web server software.
Open Graph is a protocol that is used to integrate any web page into the social graph.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
Sass is an extension of CSS that enables you to use things like variables, nested rules, inline imports and more.
WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. Features include a plugin architecture and a template system.