
If you are reading this, I assume you already know what the
Linux kernel is and why you may want to update it. However, if you are accidentally reading this walkthrough, just happen to be running Linux, and have no idea what the kernel is or why you would want to update it, the next two paragraphs are for you (if you are looking instead into a less verbose and more generic way of updating your kernel on any Linux distro,
read here). In a neophyte nutshell, the Linux kernel is the brain of the Linux system. It tells your system which file systems, hardware, protocols, etc. are supported. There is a lot more to it than that, of course, but I think that diminutive description will suffice for now.
Considering you can install the kernel source via apt, and basically just untar, copy a config files, run make oldconfig, and then run the make-kpkg stuff ... this tutorial is more like a generic kernel install than it needs to be. Plus the kernel sources gotten via apt have been patched for cramfs support so you can use the nice initrd option that is standard in debian kernels, which you don't get from vanilla sources.