From the initial decision to move Ubuntu away from GNOME to the controversial Unity 8 and Mir projects, Unity's existence has been quite turbulent. Over the years, it still grew to be a mature shell for Linux desktops, with features that are still not as good in many of its competitors, such as its HUD system. While Canonical will no longer focus on adding new features to Unity, it will still receive updates for the next couple of years, since it is a part of the latest Ubuntu LTS (Long Term Support) release, Ubuntu 16.04 Xenial Xerus.
Getting back to Unity is a simple process. If you have a fresh Ubuntu 17.10 installation, all you need to do is install Unity and switch to it, but if you upgraded from an older version of Ubuntu, then the only thing you need to do is switch back to Unity.
Method 1:Installing Unity
Since Unity is still in Ubuntu's repositories, it's very easy to install:
sudo apt update
sudo apt install unity
This will prompt you to download a big set of packages that make up the Unity shell. Once that's all installed, restart your computer – Unity will not be listed as an option unless you do that.
Method 2: Switching to Unity
The process of switching back to Unity is the same as switching to any other desktop environment. When you choose your username, press the little gear icon symbol near the sign in button, and choose Unity in the menu that pops up.
When you sign in, you'll be back to using Unity!
Did you decide to go back, or are you giving GNOME a shot? Let us know in the comments below!