Google APIs are application programming interfaces developed by Google which allow communication with Google Services and their integration to other services.
PayPal is a American international e-commerce service that enables companies and individuals to send money and to accept payments without revealing any financial details.
Previously Google Apps for Business. G Suite is a cloud-based productivity suite that helps you and your team connect and get work done from anywhere on any device. It's simple to setup, use and manage, allowing you to work smarter and focus on what really matters.
The Open Graph protocol enables any web page to become a rich object in a social graph, a open protocol supported by Facebook
Google's hosted library for web fonts. Allows websites to choose and use fonts from a free, wide variety of fonts.