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.
Polylang is a WordPress plugin which allows you to create multilingual WordPress site.
Vue.js is an open-source model–view–viewmodel JavaScript framework for building user interfaces and single-page applications.
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.
Yoast SEO is a search engine optimisation plugin for WordPress and other platforms.