In the early 2000s, we used to write a lot of CGI programs. This was the primary way to make websites dynamic at the time. These CGI programs were usually written in Perl, but sometimes in C to increase performance. The CGI mechanism is conceptually simple but powerful. When the web server receives an incoming request handled by a CGI script (e.g. GET /~jakegold/cgi-bin/guestbook.cgi), it: Sets up environment variables containing request metadata (HTTP headers, query parameters, request metho...
