The webInterface is a special folder next to the CrushFTP application.  It contains the files used to generate the CrushFTP WebinterFace when using a web browser to connect to CrushFTP using the HTTP:// protocol.  The entire WebInterface can be customized and personalized through the CrushFTP UserManager.  This allows you to brand the CrushFTP interface to look like you want.  There is a video available for download on my website that demonstrates the WebInterface abilities.  Downloads with HTTP also support resuming an interrupted download if the browser supports it, or if the Java download manager is used.  Below is an example picture of the WebInterface from my demo site: https://www.crushftp.com/demo/  (login and password is "demo".)