Linux Family OS

Linux - an operating system created by Linus Torvalds for personal computers and workstations , dated on September 17, 1991.

Linux - is a modern operating system that is compatible with POSIX, and which it is based on the operating system UNIX.

It is a multiuser network operating system with a network  graphical window system X Window System.  

Linux operating system supports both standards of open systems and protocols of the Internet. It is compatible with the Unix, DOS, MS Windows systems.