Gravatar is a service for providing globally unique avatars.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.
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.
WP Fastest Cache is one of a number of plugins for WordPress designed to accelerate the performance of your website.
WPML plugin makes it possible to build and run fully multilingual WordPress sites.