Google PageSpeed is a family of tools designed to help websites performance optimisations.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
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.
Typekit is an online service which offers a subscription library of fonts.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.