Activists of the GNU Project insist on the fact that what is commonly refered to as Linux should be more accurately called GNU/Linux (see GNU/Linux) which includes the Linux kernel and supporting software (editors, compilers, tools) from the GNU project.
In fact, the GNU Hurd is a set of microkernel servers that can be used to replace the Linux kernel on GNU systems.
Just keep that in mind when you are mentioning Linux, especially when you are around GNU/Linux purists 
Note that projects like KDE are not the same thing as GNU because they provide applications that run on top of the core GNU Operating System.
Writing GNU/Linux instead of Linux always made me think I was wasting keystrokes until I read this text by Richard Stallman called: SCO smear campaign can't defeat GNU community. This make me think twice about the consequences of simply writing Linux. Only a fool can't change his mind. -- FrancoisDenisGonthier