Linux or GNU / Linux refers to a bunch of operating systems packaged with the Linux kernel, especially GNU and other components. Typically , desktops and servers are packaged in a form called Linux , Distribution or Distro for both uses. The defining component of a Linux distribution is the Linux kernel , [ 6] an operating system kernel and Linus Torvalds first released on September 18 , 1991. [6] [8] [9] Many Linux distributors use the term Linux in their operating system names, and the Free Software Foundation uses the term GNU / Linux to refer to the operating system family.