XSane is a graphical scanning frontend. It uses the SANE-library to talk to scanners. This means that XSane does not support any scanners itself.
XSane is designed for acquiring images with scanners (there are other devices like cameras and videodevices supported by SANE, but XSane is not designed for that purpose). You can scan to file, do a photocopy, create a fax, create and send a mail and start XSane from the GIMP as gimp plug in.