I've looked through the Nagios documentation and see hundreds of references to CGI's (it just assumed you know what they are because their appears to be no definition), and to a CGI.CFG file. I can see from the documentaiton that these are used to display information on a webserver such as Apache. But what is a CGI? I'm not overly familiar with web servers and terminology - so is a CGI an industry standard akronym or something unique to Nagios? What does CGI stand for?