According to the manual page for
apt-get it indicates;
APT-GET(8) APT APT-GET(8)
apt-get - APT package handling utility -- command-line interface
remove is identical to install except that packages are removed
instead of installed. Note the removing a package leaves its
configuration files in system. If a plus sign is appended to the
package name (with no intervening space), the identified package
will be installed instead of removed.
purge is identical to remove except that packages are removed and
purged (any configuration files are deleted too).
That explains the difference between
remove will only remove the package whilst not touching nor changing the config files where
purge will remove everything relating to the package including the configuration files.
Having said that;
clipit* with a
* indicates that it will remove the said package & all its includes (config files.. etc) accordingly.
remove - If you're removing skype, chrome.. etc or any other package that holds configuration files inside your
/home/user directory. Those will not be removed.
purge - Further, if you use this on bind, mysql, squid.. etc or any packages that stores configuration files in their respective location such as
/etc.. well, those will be deleted.