Amazon Advertising (formerly AMS or Amazon Marketing Services) is a service that works in a similar way to pay-per-click ads on Google.
eBay Partner Network is an online referral program where eBay pays commissions to referrers on sales generated by customers they’ve referred.
Google Font API is a web service that supports open-source font files that can be used on your web designs.
Google Hosted Libraries is a stable, reliable, high-speed, globally available content distribution network for the most popular, open-source JavaScript libraries.
jQuery is a JavaScript library which is a free, open-source software designed to simplify HTML DOM tree traversal and manipulation, as well as event handling, CSS animation, and Ajax.