How exactly does hibernation work?

[Mini-Me]

I use hibernation on most of my XP boxes - it generally saves heaps of time booting up.

I would like to know exactly how this works.

My theroy is that when hibernation is triggered(usually by pressing the power button), the computer creates a bootable image on the hard drive. This image contains everything in RAM + everything in the HDD cache. Seeing as nothing will have changed(or should not have changed) since the machine went into hibernation, the system simply re-loads a 200MB+ bootable image file when the power button is next pressed. This image file contains the initalized running version of the OS kernel, and all the drivers already configured.

I could be 100% wrong, so could someone chime in and explain exactly how hibernation work and what is going on during: (A) the screen where it says:"Preparing to hibernate...", and (B) the screen where it says: "Restoring Windows..." when you next power up.

Thanks!
:)

[Paul Komski]

A bootable image is not created but the RAM is dumped to a file which is reloaded on the next normal startup.

http://en.wikipedia.org/wiki/Hibernate_%28OS_feature%29
http://en.wikipedia.org/wiki/Features_new_to_Windows_XP#Hibernate_mode

[Mini-Me]

Thanks for the links - that's great! :)