Apache is a free and open-source cross-platform web server software.
cdnjs is a free distributed JS library delivery service.
Chart.js is an open-source JavaScript library that allows you to draw different types of charts by using the HTML5 canvas element.
Open Graph is a protocol that is used to integrate any web page into the social graph.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.