Preparing a Hard Disk for Use

After you have physically installed the hard disk and configured CMOS Setup to recognize it, that drive must still be prepared before it can store data. This process requires three steps:

Low-level formatting

Low-level formatting, also called physical formatting, records the tracks and sectors that are used to store data. Low-level formatting occurs at the hardware level, and is independent of the way that the disk will be divided and of the operating system that will use it. All ATA and most SCSI drives are low-level formatted at the factory, so you may not need to perform this step yourself.


Partitioning divides the physical disk into one or more logical sections, each of which will contain one or more logical volumes identified by drive letter. Any hard disk must contain at least one partition with at least one volume. Any new hard drive must be partitioned before it can be used.

Logical formatting

Logical formatting, also called high-level formatting or DOS formatting, creates within the volume the logical disk structure (called the filesystem) needed by a particular operating system to store its data. Drives that will be accessed by DOS, Windows 3.X, and Windows 9X use the FAT filesystem (which comes in several variants). Windows NT/2000 uses either FAT or NTFS filesystems.

The following sections examine each of these steps in turn.

Low-Level Formatting

Low-level formatting a hard drive lays down the tracks and sectors that will be ...

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