I have a general question, maybe from lacking time to dig into the man pages or getting more personal with Python, Perl and C-shell scripts but here it goes.

When Linux boots, it is booting from an .img file that holds the Kernel image. In the kernel image there are modules compiled. When you install or uninstall modules, you are required to replace the RAM image or the memory image with mkinitrd command....

Can someone with uber understanding of how this process occurs share "in plain English, I hope" their valuable knowledge and let us know how Kernel image relates to the image in ramdisk, and why is this necessary, what does it do on the OS level.

Thanks a bunch.

I don't have an "uber" understanding, but you can get a lot better understanding by purposefully breaking it. Namely, install two or more different versions of a kernel (like i486 and i686) and then modify grub to mismatch the kernel and initrd.img files. See what breaks. Play around in busybox. See what hardware no longer works (the first time I made the mistake, the mouse didn't work and it took me a while to figure out what mistake I made).

I gained a lot of understanding of what was going on in initrd.img when I wanted to modify the booting process to load the entire OS into RAM instead of merely mounting the root partition directly. I read a lot of scripts in the /usr/share/initramfs-tools/ directory tree until I finally found the script I'd modify (/usr/share/initramfs-tools/scripts/local/). In all cases, the "head honcho" is "init". Everything else is ultimately started from init.

Nope. None of my systems (built by me) use initrd.
A very minor amount of effort on your part would have found this in wikipedia.
Plenty of other references exist as well.