After removing, installing new or upgrading packages, there are some (not always) packages not needed any more.
They can be safety removed from the system. Every command has to be run with root privileges su or sudo.
After upgrading packages, the package manager store all deb packages even it doesn't need them any more.
To remove all old deb's from the system (the latest deb versions will be NOT removed), run:
If you would to remove all the deb packages from the system, run: