Apache is a free and open-source cross-platform web server software.
Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PHP is a general-purpose scripting language used for web development.
SPIP is a content management system written in PHP that uses one or more databases like SQL, SQLite or PostgreSQL.
Twitter is a 'microblogging' system that allows you to send and receive short posts called tweets.