After formatting logical disks are organized as follows:
• Logical disks start with the boot sector;
• One or several copies of file allocation table (FAT) are placed after the
boot sector;
• Next goes the root folder;
• Next goes the data area.
Each logical disk has to be formatted with FORMAT separately.
A.8 File Systems
The logical structure that has been created on the hard disk is supported by
means of operating system. The file system itself presents the information on
the disk as an ensemble of files and folders.
From the user’s point of view a file is a unit of storage of logically connected
information: texts, graphics, sound. As for data storage organization, a file is
a chain of connected sectors or clusters. A cluster is a unit of several sectors.
(Sectors are characteristic for file systems supported by various versions of
Windows.)
Operating systems support file systems on hard disks (or disk partitions) by
allowing to create, copy, and delete files and folders.
At present, the most widely spread file systems for PCs are the following
two:
• FAT16/FAT32 (File Allocation Table) for DOS, OS/2, Wid-
ows 95/98/Me/NT/2000/XP;
• NTFS (Windows NT File System) for Windows NT/2000/XP.
However, there are many more other file systems. Linux operating system,
which is now gaining popularity, widely uses two file systems:
• Ext2 is a file system for end-users’ PCs;
• Ext3 is the default file system used by Red Hat Linux;
• ReiserFS is a more secure (with respect to data integrity) file system
that is used on data servers.
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