From Xojo Documentation
Returns the value of the HTTP header specified. Depending on the deployment mode, not all HTTP headers are available. In Stand-Alone deployments, all HTTP headers are always available. In CGI deployments, many of the headers are not provided to your app.
The available headers in CGI mode are:
|User-Agent||Describes the browser the user is running.|
|Cookie||The cookie values provided by the browser.|
|Host||The domain the application is running on, such as 'subdomain.mydomain.com'.|
|Accept||The MIME types the browser is capable of receiving.|
|Accept-Language||The languages the user would prefer to receive.|
|Accept-Encoding||The encoding methods the browser is capable of receiving.|
|Connection||Either 'keep-alive' or 'close' depending on wether or not the browser intends to keep the connection alive for reuse later.|
|HTTPS||Set to 'on' if the connection is secure, blank or 'off' otherwise.|
|SCRIPT_NAME||The virtual path where your app is running, such as '/myapp/myapp.cgi'.|
This list is not meant to fully describe these headers. For more information on any particular header, please do a search online, there is plenty of good information available.