May 28, 2014, 11:36 AM — LightDM is a display manager used by various Ubuntu spins. Here's how you can install it in Ubuntu 14.04.
1. Open a terminal window.
2. Type in the following commands then hit Enter after each.
sudo add-apt-repository ppa:lightdm-gtk-greeter-team/stable
sudo apt-get update
sudo apt-get install lightdm-gtk-greeter
3. Use this command to restart your system.