Apache is a free and open-source cross-platform web server software.
Google Hosted Libraries is a stable, reliable, high-speed, globally available content distribution network for the most popular, open-source JavaScript libraries.
Open Graph is a protocol that is used to integrate any web page into the social graph.
PayPal is an online payments system that supports online money transfers and serves as an electronic alternative to traditional paper methods like checks and money orders.
Prototype is a JavaScript Framework that aims to ease development of web applications.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.