Linux

Linux is a free and open-source monolithic kernel  created by Linus Torvalds in 1991. Unlike BSD Flavours( FreeBSD, OpenBSD  and  NetBSD  Linux is not a full operating system; it is only a kernel and is packaged with other tools and utilities into a "distribution" or distro. Examples of these distros are  Debian ,  Fedora ,  Boop!_OS  and  risiOS . Linux is licensed under GNU  GPL-2.