
To clean some packages laying around, run the following:
root@test-VirtualBox:#sudo apt-get autoremove
root@test-VirtualBox:#sudo apt-get clean
root@test-VirtualBox:#sudo apt-get autoclean
Alternately, you can use;
root@test-VirtualBox:#sudo apt-get remove packagename
where the package name is the package you wish to remove
These commands are needed to remove packages (dependencies) laying on the system after a particular package has been uninstalled.