Common Gateway Interface

Interface between Web servers and external programs

In computing, Common Gateway Interface (CGI) is an interface specification that enables web servers to execute an external program to process HTTP or HTTPS user requests. Such programs are often written in a scripting language and are commonly referred to as CGI scripts, but they may include compiled programs. A typical use case occurs when a web user submits a web form on a web page that uses CGI. The form's data is sent to the web server within an HTTP request with a URL denoting a CGI script.

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