Apache is a free and open-source cross-platform web server software.
JSDelivr is a free public CDN for open-source projects. It can serve web files directly from the npm registry and GitHub repositories without any configuration.
KaTeX is a cross-browser JavaScript library that displays mathematical notation in web browsers.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Ubuntu is a free and open-source operating system on Linux for the enterprise server, desktop, cloud, and IoT.
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.