The GNU stands for GNU's Not Unix. It is a project as described in GNU.
What can be confusing is the usage. GNU can stand for:
- an entire system as envisioned in 1983. GNU/Hurd is a synonym.
- GNU components when used with the Linux kernel: GNU/Linux This term has been adopted by the Debian project but is not recognized as widely as the FSF would like.
-- ?GrantBow - 03 Mar 2004