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.
Lightbox is small javascript library used to overlay images on top of the current page.
Modernizr is a JavaScript library that detects the features available in a user's browser.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.