UNIX is a Multi-User, Multi-Tasking and Multi-Processing operating system. It has the capability of handling multiple users at the same time. It is a CUI based operating system. It is robust and secured. The source code is open is Unix. Unix is developed in C language. Multiple programs can run at the same time in Unix, hence it is called as multi-tasking. As it is open source hence the source code can be changed with different flavors of Unix. The different flavor of Unix is Linux, Sun Solaris, HP UX.Signup and Attend Linux Unix Online Training Classes by Experts.