| Variable name | Description |
| GATEWAY_INTERFACE | The CGI version |
| REQUEST_METHOD | GETor POST |
| SCRIPT_NAME | Relative URL of the running CGI program |
| QUERY_STRING | The GETmethod query string |
| SERVER_SOFTWARE | Name and version of the Server software |
| SERVER_NAME | Host name of the server |
| SERVER_PROTOCOL | Protocol and version running on the server (e.g. HTTP/1.0) |
| SERVER_PORT | The port number of the server |
| HTTP_USER_AGENT | Name and version of the client (e.g. Mozilla/3.01 for Netscape Navigator 3.01) |
| HTTP_ACCEPT | MIME types accepted by the browser |
| PATH_INFO | "Extra Path" information passed on the URL |
| PATH_TRANSLATED | PATH_INFOmade relative to the server's root directory |
| REMOTE_HOST | Machine name of the remote host |
| REMOTE_ADDR | IP address of the remote host |
| REMOTE_USER | If this connection is authenticated, this is the authenticated user name. |
| REMOTE_IDENT | For RFC 931 "identd" connections |
| AUTH_TYPE | The type of authentication in effect (if any) |
| CONTENT_TYPE | MIME-type for POSTmethod query |
| CONTENT_LENGTH | Length of query POSTmethod |