cdnjs is a free distributed JS library delivery service.
Font Awesome is a font and icon toolkit based on CSS and Less.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
LiteSpeed is a high-scalability web server.
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.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.