Apache is a free and open-source cross-platform web server software.
Linkedin Sign-In is an authentication system that reduces the burden of login for users, by enabling them to sign in with their Linkedin account.
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.
Pinterest is an image sharing and social media service designed to enable saving and discovery of information.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.