Apache is a free and open-source cross-platform web server software.
Contao is an open source CMS that allows you to create websites and scalable web applications.
Modernizr is a JavaScript library that detects the features available in a user's browser.
PHP is a general-purpose scripting language used for web development.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.