Possible Duplicate:
What does Format Do?
I've been formatting all matter of media for years, but I'm unclear on what exactly formatting even is. I know that it prepares the disk to be used and I know that you can format disks in different ways for different purposes and operating systems, but beyond knowing I should use format style ABC for operating system XYZ, I have absolutely no idea what the formatting process actually is.
What does formatting a hard drive actually do to the hard drive? How is a raw and unformatted disk right out of the box different from a hard drive that I've formatted for use? And for that matter, what's the difference between quick format tools that complete the process in seconds versus more in-depth formatting that takes hours on a large disk?