Found it
http://www.gnu.org/gnu/linux-and-gnu.html

Hope this will clarify things (better than what I did )

Ginux

So what your saying is Linux is generally the same but appears differently because the INSTALL compiles it to the system? So distro's such as Mandrake, have a different Linux kernel only because the "INSTALL" compiles the source differently? If this was to be done manually, it the kernel could be the same or different, pending on the user?

That's a very true statement. They all install a custom configured or different version of a kernel, but a kernel is still just a kernel.

The packages are mostly GNU, and the init scripts are usually specific to the distro.

I have used multiple distros on the same machine when trying some out and they all used the very same kernel, which I compiled for my system. They were all setup to use the same /boot partition, where I had different kernels to choose from.

So the 2 major features seen between distros is:

1) The version of the kernel vs the distro's release
2) How the distro's scripts compile the kernel's GNU source to your system


So for someone who doesn't know how to compile, and relies on the install to do it, the outcome on a kernel from Mandrake and the out come on a kernel from Redhat would not be the same?

With respect to the kernel yes.

The kernel config or version may have a huge bearing on how the hardware you have will work or not and how well.

Of course if this thing is installed and working we assume it's transparent and really has no purpose other than making the software work with the hardware.

The real differences in the distros are the packages they come bundled with and how they are configured. The configuration tools that are developed by the distro that have their own traits. The startup or init scripts that are used to start services on the computer when it boots or changes runlevels. The media, logos, pictures, maybe sound files, etc. The support, updates, installation help, etc. The install image itself, which is usually a working system image that boots form cd, dvd, or floppy. It runs in ram and from the install media, giving you the tools to format your drives and install the binaries that will become the installed system.

I have seen problems. I would say that the main problem would be the filesystem and the use of devfs.

If the default install for one distro uses a filesystem that's not supported by the other you will need to rebuild the kernel. Likewise if one uses devfs and the kernel of the other does not support it you will need to rebuild.

The /usr/lib/modules folder on each distro must have the folder with the kernels modules in it. So you will need to copy that folder to each installed system to use the kernel, or have a /usr/lib/modules partition and mount it in all distros. Along with that if you find module loading problems you may need a custom script to load modules. That's not really to do with different distros though as the same problem could exist on a single distro with multiple kernels.



When you go to a 2.6 kernel there are a lot of other things that will be different from your working system with 2.4 kernels. Some scripts will most likely need to be modified as well as a different kernel-utils package, which is required on any distro.

I see. Note taken then. Thanks.