How to uninstall or remove lightdm-gtk-greeter software package from Ubuntu 14.04 LTS (Trusty Tahr)

You can uninstall or removes an installed lightdm-gtk-greeter package itself from Ubuntu 14.04 LTS (Trusty Tahr) through the terminal,

$ sudo apt-get remove lightdm-gtk-greeter

Uninstall lightdm-gtk-greeter including dependent package

If you would like to remove lightdm-gtk-greeter and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove lightdm-gtk-greeter

Use Purging lightdm-gtk-greeter

If you use with purge options to lightdm-gtk-greeter package all the configuration and dependent packages will be removed.

$ sudo apt-get purge lightdm-gtk-greeter

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove lightdm-gtk-greeter