GNU/Linux naming controversy lacking. The GNU kernel was called GNU Hurd. The Hurd followed an ambitious design which proved unexpectedly difficult to implement and has only been marginally usable. Independently, in 1991, Linus Torvalds released the first version of the Linux kernel. Early Linux developers ported GNU code, including the GNU C Compiler, to the kernel. The free software community adopted the use of the Linux kernel as the missing kernel for the GNU operating system. This work filled the remaining gaps in providing a completely free operating system. Over the next few years, several suggestions arose for naming operating systems using the
Linux free software. Work began in 1984. Later, in 1985, Stallman started the Free Software Foundation and wrote the GNU General Public License (GNU GPL) in 1989. By the early 1990s, many of the programs required in an operating system (such as libraries, compilers, text editors, a Unix shell, and a windowing system) were completed, although low-level elements such as device drivers, daemons, and the kernel, called GNU/Hurd, were stalled and incomplete. Linus Torvalds has stated that if the GNU kernel had been available at the time (1991), he would not have decided to write his own. Although not released until