Page 75 - Computer - 10(A&B)

Write T for True and F for False statements.

1. Taskbar shows the name of the opened application.
2. The Maximize button displays the window on full screen.

3. Windows is an example of a GUI Operating System.

Session 2

File Systems

A computer system cannot store all information a user needs in its primary memory,
RAM, due to its size restrictions. Thus, we need secondary storage devices such
as hard disk, CD/DVD, pen drives, memory cards, or network storage. Let us
understand how the computer stores and manages information.
Every physical secondary storage device (hard disk, DVD, pen drive, etc.) is divided
into tracks and sectors. Tracks are concentric circles on a disk whereas sectors are
small sections on each track. A group of contiguous sectors is called a cluster. The
size of each sector is fixed. Thus, a fixed amount of data can be stored on one part
of a disk.
All information in a computer is stored in form of files. A file is nothing but a location on the disk where the data
is stored. The entire contents of a file may be saved at a single location or broken up into segments, with each
segment stored at different locations. It is the responsibility of the operating system to collect all parts of a file
from various locations and display it as one unit to the user. This is managed by the operating system through a
file management system. A file system is the part of the operating system that is responsible for managing files
and the resources on which it resides.

Basic Functions of File System
A file system performs the following functions:

v Presents a logical or abstract view of files and directories to the users by hiding the physical details of
secondary storage devices and the I/O operations for communicating with the devices.
v Facilitates efficient use of the underlying storage devices.
v Supports sharing of files among different users and applications. This includes providing protection
mechanisms to ensure that information is exchanged in a controlled and secure manner.
A file is given a name when it is stored. The file name to the user is a sequence of characters such as
“MyFirstDocument.docx”, but internally it stores the addresses of the locations where the data of the file is
stored on the disk. Apart from the file location, the file also stores information about the type, size, owner, status,
access permissions, and current state of a file.
The file system keeps track of all files and their attributes to perform its functions. File systems typically have
directories which associate file names with files, usually by connecting the file name to an index into a file
allocation table of some sort, such as the FAT in an MS DOS file system, NTFS in Windows or an inode in a
UNIX file system.

File System Structure
Every file system uses a specific structure and system for creating, storing,
and accessing files. It also provides routines to add and manipulate the data
contained in the files. Most file systems provide the facility of creating folders
or directories under which files can be stored.
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