Zorin OS 15 is based on Ubuntu 18.04.2 Long Term Support. However, much of Zorin OS’ connection to Ubuntu stays under the hood. What you see on top is a solidly designed computing platform that lets you work without distractions or frustrations.
The so-called Zorin Desktop is based on an integration of the GNOME shell. However, Zorin’s spin on integrating GNOME goes far beyond a plain GNOME desktop design. The Zorin desktop integrates a Windows 7 appearance that makes the way GNOME works familiar and comfortable, especially to those migrating from that other computing platform.