Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
OpenStreetMap is a free, editable map of the whole world that is being built by volunteers largely from scratch and released with an open-content license.
PHP is a general-purpose scripting language used for web development.
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.