Zorin OS is an operating system targeted to new converts from Windows to Linux. It eases up the transition, because gives the user a familiar interface.
As I wrote before, Zorin OS is based on Ubuntu and, until version 6, on GNOME 2 functionality. It means system resource requirements are quite high.
But what if your computer is not the newest one? Does it mean Zorin OS is not available for you? Not at all! The Zorin team releases a special edition for people like you: this is the Lite version. This operating system uses the LXDE desktop environment, not the GNOME one.