Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
cdnjs is a free distributed JS library delivery service.
Internet Information Services (IIS) is an extensible web server software created by Microsoft for use with the Windows NT family.
ipify is a service which provide public IP address API, IP geolocation API, VPN and Proxy detection API products.
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.
ASP.NET is an open-source, server-side web-application framework designed for web development to produce dynamic web pages.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.