User Guide

Hard Disk And File Systems

A.8 File Systems

The logical structure that has been created on the hard disk is supported by means of the

operating system. The file system itself presents the information on the disk as an

ensemble of files and folders.

For the user, a file is a unit of storage of logically connected information, including texts,

graphics, and sound. 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 you

to create, copy and delete files and folders.

At present, the most widely used file systems for PCs are the following two:

• FAT16/FAT32 (file allocation table) for DOS, OS/2 and

Windows 95/98/Me/NT/2000/XP;

• NTFS (Windows NT file system) for Windows NT/2000/XP.

However, there are many other file systems. The Linux operating system, which is now

gaining popularity, widely uses three 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

A.9 File System Main Specifications

Operating systems allow you to work with data by supporting a file system on a disk

partition.

All file systems contain structures required for data storage and control. These structures

usually consist of an OS boot record, files and folders. A file system performs the

following main functions:

1. Monitors used and free disk space (including bad sectors)

2. Maintains folders and file names

3. Monitors physical file location on a disk

Different operating systems use different file systems. One operating system may support

only one file system; others may support several.

A.9.1 File system specification summary

Below is a summary of the most popular file systems. Each system is briefly discussed.

This information can help you work with Acronis Disk Director Server.