Format Hard Drive - A Webopedia How To Guide
Last Updated: 07-20-2011 , Posted: 10-03-2010
Format actually means to prepare a storage medium, usually a hard drive, for reading and writing. When you format hard drive, the operating system erases all bookkeeping information on the disk, tests the disk to make sure all sectors are reliable, marks bad sectors, and creates internal address tables that it later uses to locate information.
When do you need to be concerned with formatting hard disk drive? If you're installing a new hard drive for the first time, removing errors from your hard drive, trying to get rid of a nasty virus, or even cleaning your hard drive to sell or donate your computer are a few of the many reasons why one might need to format a hard drive.
The term format actually means to prepare a storage medium (usually a hard drive or disk) for reading and writing. When you format a hard drive the operating system erases all "bookkeeping" information on the disk, then it tests the hard drive to make sure all sectors are reliable, marks bad sectors (that is, those that are scratched or otherwise damaged), and creates internal address tables that it later uses to locate information. You must format a hard drive (floppy or hard disk) before you can use it.
Format or Reformat? The Phrase Explained
Some people say they are "formating a hard drive," while others might say they are "reformatting a hard drive."
The correct terminology goes like this: The first time the procedure is performed on a drive it is called formatting. When you take a hard drive that has been previously formatted and run it through the format process again, it is referred to, logically, as reformatting.
Before you Format Backup the Hard Drive
Before you can format a hard drive look at why you need the process done. If your objective is hard drive recovery, the first step will be to back up as much personal data and information from your hard drive as you need. When a hard drive format is planned ahead of time you certainly can copy and archive data off your hard drive before you start the format process. If your objective is to wipe and reload due to a virus that has already caused serious system damage, a backup might not be possible.
How to Format Hard Drive
If you purchased your computer from a systems vendor -- such as a Dell, HP Compaq or Gateway system -- you most likely will have a setup or a restore-and-recovery CD (also referred to as a master CD) that came with the system. If this is the type of system you use, then a format is an easy process. The master CD will complete the format hard drive process, put the Windows operating system onto the computer for you, and also install any software and programs that came with the pre-configured computer system. If you no longer have your master set-up CD, you should contact the manufacturer to get a replacement.
If you aren't using a pre-configured "brand" computer system then the process to format hard drive will consist of you formatting the hard drive manually, installing your Windows OS from CD, then installing your software programs and hardware drivers. Before you begin the formatting process, it is important to make sure you have all the drivers for your hardware located, the Windows CD and ant software to ensure a smooth setup.
It's also important to know about your operating system before you format. If you're going to be putting a much older version of the Windows operating system -- such as Windows 98 or Windows ME -- then you should have a Windows 98 or ME start-up disk to complete the procedure. In this instance, you would restart the system with the start-up floppy disk in the drive. Upon system boot, you will choose to have CD-ROM support. Once the files load you can then choose to run the format command on your main drive (usually C drive but not always so check first). If you are using Windows 2000, Windows XP or Windows Vista, the Windows installation process offers "format your hard drive" as an option. Here you would ensure your computer is set to boot from CD-ROM (a setting in your system BIOS), insert the Windows CD and restart the computer. From there you will be on your way to format the hard drive.
The Format Command
Format is a Microsoft DOS command. It's the command line you run to remove information from a computer disk, floppy disk or hard disk. It is an external command found in many of the Windows Operating systems. The format hard drive process is done in three steps:
Low-level formatting creates the physical structure on the hard drive. Partitioning divides the hard drive into logical pieces that become volumes. High-level formatting defines the logical structures on the partition and places at the start of the disk any necessary operating system files.
The format command syntax is the following:
FORMAT drive: [/parameters]
where drive: specifies the volume to format (the hard disk letter followed by a colon) — example format c:
— where [parameters] formats the disk with different options — example format c: /s will copy system files to the formatted disk or format c: /q performs a quick format.
The syntax used between Windows 95, 98 and ME differ slightly from Windows 2000, XP and Vista. To see the available Format command parameters for your operating system, you can type FORMAT /? at the DOS command line.
- Click to view a screen shot of format commands for Windows XP
- Click to view a screen shot of format commands for Windows Vista
Does Format Hard Drive Really Erase All Data?
Remember that "format" and "delete" do not mean erase!
When you format or reformat a hard drive it doesn't erase the data on the hard drive -- only the address tables. In a case where you have accidentally completed a format hard drive, a computer specialist may be able to recover most or all of the data that was on the drive.
Keeping in mid that data can be pulled from a newly formatted hard drive with the right tools, for any business or corporation that is planning to donate old computers to charity, this could pose a security risk if the hard drive contained confidential business information.
Remember — just because you may donate the computer to charity that doesn't mean an honest person will end up with the hard drive. While that shouldn't deter you from recycling old computers in this way, it should be an incentive to ensure all business data has been completely wiped from the hard drive. Never just delete the files and assume they are gone because you can't see them on the hard drive. Businesses should at the very least run the format command to erase the hard drive.
For a higher level of security we recommend you read the following Webopedia article:
- Editor's Recommendation: Learn How to Completely Erase a Hard Disk Drive
The safest method to completely remove data is to overwrite the disk. You can do this yourself, although it is time consuming. To overwrite the disk would mean to format, then fill the disk completely with data, and format again. The easiest way to do this is to use a software program that will overwrite the disk for you. Most of these programs, often referred to as "Data Dump" software, meet the strict deletion requirements of the U.S. military. As an added bonus, a few good data dump programs can be freely downloaded from the Internet. Several Data Dump programs can be found in our list of reference links below.
Understanding The Format Hard Drive Process
The following Webopedia term definitions will help you to better understand how to format a hard drive.
Related Term Definitions on Webopedia:
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Did You Know...???
In 2003 two MIT students purchased 158 used disk drives from various locations and found more than 5,000 credit card numbers, medical reports, detailed personal and corporate financial information, and several gigabytes worth of personal e-mail and pornography on those drives. [Source]