Does Formatting Really erase All Data?

Reformatting a disk does not erase the data on the disk, only the address tables. The good news is that if you accidentally reformat a hard disk, a computer specialist should be able to recover most or all the data that was on the disk. The bad news is that for any business or corporation that is planning to donate old computers to charity, this could pose a security risk if that computer disk 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 it. 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. The safest method to completely remove data is to overwrite the disk. You can do this yourself, although it is quite 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, which are often referred to as "Data Dump" software, will meet even 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.

The Format Command

Format is a Microsoft DOS command. It's a command line you can 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. Hard drive formatting is done in three steps:

(1) 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 and XP. To see the available Format command parameters for your operating system, you can type FORMAT /? at the DOS command line.

Formatting a Hard Disk Drive

When installing a hard disk drive (commonly called a hard drive) for the first time, attempting to remove errors from your drive, getting rid of a nasty virus, or even cleaning a hard drive because you are selling or donating your computer -- those are just a few of the many reasons why one might consider formatting their hard drive.

Format actually means to prepare a storage medium, usually a disk, for reading and writing. When you format a disk, the operating system erases all bookkeeping information on the disk, tests the disk 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 disk (floppy or hard disk) before you can use it.

When you take a disk that has been formatted and run it through the format process again, it is referred to, logically, as "reformatting".

Key Steps to Formatting

Back it Up!Before the format process, you want to make sure that if your goal is hard drive recovery, you back up as much personal data and information from your hard drive as you need. In some instances where a virus has caused serious system damage, this may not be possible, but if your format is planned ahead of time you certainly can copy and archive data off your hard drive before you start the format process.

How to Format

If you purchased your computer from systems vendor such as a Dell , HP Compaq or Gateway system, you most likely will have a set-up or a restore-and-recovery CD (also referred to as a master CD) which came with the system. If this is the type of system you use, then a format is an easy process as the master CD will format the hard drive, reinstall your Windows operating system, and install any software and programs which came with the 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 this type of mass-market system, then a hard drive format 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 your driver CDs located, Windows CD and your software CDs to ensure a smooth set-up.

It's also important to know about your operating system before you format. For example, if you're going to be reinstalling 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 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). If you are using Windows 2000 or Windows XP, 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 reformatting.