Whys and hows of initrds

[grfgguvf]

Hi,
I don't know if the LKML is a technical kernel development list or a
newbie support list (or both?) so maybe I'm posting to the wrong
place.

Questions:
* Why is an initrd needed?
* What does it do?
* What are the differences between an initrd and an initramdisk (if
any)? And an initramfs?
* Why cannot the task of initrds be done more easily?
* Why don't other operating systems need an equivalent? Or do they?

Opinions and technical explanations welcome. Please, no excessive flames!

I have searched the FAQs, HOWTOs and guides on tldp.org, but it seems
to me there is no "initrd FAQ". If I just didn't find it then I
welcome any pointers and sorry for wasting time...
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/