Modernizr is a JavaScript library that detects HTML5 and CSS3 features in the user’s browser and allows you to target specific browser functionality in your stylesheet.
Google APIs are application programming interfaces developed by Google which allow communication with Google Services and their integration to other services.
nginx [engine x] is a HTTP server and mail proxy server written by Igor Sysoev.
PHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML.
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.
Content Security Policy is best used as defense-in-depth, to reduce the harm caused by content injection attacks.
UTF-8 (8-bit UCS/Unicode Transformation Format) is a variable-length character encoding for Unicode. It is the preferred encoding for web pages.
The http-equiv attribute provides an HTTP header for the information/value of the content attribute. The http-equiv attribute can be used to simulate an HTTP response header.