Unix Linux Unix is an Operating System and Linux is mainly a Kernel for Linux Based OS. Linux is a Unix-Like based OS, it means the core functionalities behind is similar to UNIX OS. Unix is an operating system having some common command as that of Linux. Linux is an operating system having some common command as that of Unix. Unix uses Command Line Interface. Linux uses Graphical User Interface with an optional Command Line Interface. Unix is mainly used in Server Systems, Mainframes and High-End Computers Linux is mainly used in Home Based PC, Mobile Phones, Desktops, etc. Unix has a rigid requirement of the Hardware. Hence, cannot be installed on every other machine. Linux is very flexible and can be installed on most of the Home Based Pcs. Different Versions of Unix are: AIS, HP-UX, BSD, Iris, etc. Different Versions of Linux are: Ubuntu, Debian, OpenSuse, Redhat, Solaris, etc. Both Unix are written in C & Assembly language. Both Linux are written in C & Assembly language.