Remove removes the program, -purge also removes the config files--r or -remove remove everything except configuration files. this may avoid having to reconfigure the package if it is reinstalled later. (configuration files are the files listed in the debian/conffiles control file). ?p or ??purge removes everything, including configuration files. if -a or -pending is given instead of a package name, then all packages unpacked, but marked to be removed or purged in file /var/lib/dpkg/status, are removed or purged, respectively.