Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!apple!usc!sdd.hp.com!elroy.jpl.nasa.gov!peregrine!ccicpg!mahrk From: mahrk@ccicpg.UUCP (MHR {who?}) Newsgroups: comp.os.msdos.programmer Subject: Re: What is low-level/high-level FORMAT? Summary: Here you go. Message-ID: <12052@ccicpg.UUCP> Date: 17 Jan 91 20:07:17 GMT References: <61737@brunix.UUCP> Organization: ICL North America Lines: 51 In <61737@brunix.UUCP>, hleaves@ruby.vcu.edu writes: > I have a few questions about formatting disks. Any responses would be > appreciated... > > 1. What is a low-level format? What does it do? (that is not done by a > high-level format) > An unformatted disk contains no flux changes on it, and hence no information which has any meaning. A low-level format writes sector information on the disk so that it can be read and written by the driving software in a meaningful fashion. This also usually destroys any other information which may have previously been recorded on the disk. > 2. What is a high-level format? What does it do? > In MS-DOS (only), this is the second stage formatting done on hard disks which divides up a (previously low-level formatted and FDISK'd) partition of the disk into the peculiar arrangement MS-DOS uses for its information. > 3. Are hard disks formatted differently than floppy disks? (is a floppy > formatted at a low-level, where as a hard disk is formatted at a high-level?) > Yes and no, in that order. Hard disks are formatted at the low level by either the factory, a piece of code contained in your disk controller's BIOS or the ROM-BIOS (for dumb controllers), or a smart formatting program for your disk, or some combination thereof. Then you have to run FDISK to partition the disk, and how many and what size depend on your version of MS-DOS and other disk support software you may have. Then the FORMAT program does the high-level format on the disk. For floppy disks, the FORMAT program does both the low and high level formats at the same time (more or less). > 4. I understand that the MS-DOS format command only performs a high-level > format of hard disks. Does it do the same thing for floppy disks? > See #3. > Thanks in advance, > Hugh > You're welcome. If I made any significant mistakes or misstatements here, corrections are welcome. If you want to be picky, use email please. -- Mark A. Hull-Richter UUCP: ccicpg!mahrk Clever remark stolen from ICL North America InterNet: [coming soon] another netter: 9801 Muirlands Blvd Go ahead, flame me. I have Irvine, CA 92713 (714)458-7282x4539 a /dev/null on my machine.